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1
Bjørnsson, Naja. „Checkpointets betydningsfuldhed“. Babylon Nordisk tidsskrift for Midtøstenstudier, Nr. 1 (20.01.2022): 20–33. http://dx.doi.org/10.5617/ba.9391.
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Checkpointet med sine sandsække og rifler, og soldatens mistænksomme blik, når han sammenligner billedet på dit id-kort med dine utydelige ansigtstræk bag bilruden. Checkpointet der aldrig fanger vores opmærksomhed i krigsfilm, fordi det kun optræder som en overgang fra én scene til den næste.
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Giverts, P. V. „CRIMINALISTIC RESEARCH ON AIRSOFT RIFLES MODIFIED FOR SHOOTING CARTRIDGES OF THE CALIBER 5.56×45 MM“. Theory and Practice of Forensic Science and Criminalistics 18 (26.12.2018): 301–8. http://dx.doi.org/10.32353/khrife.2018.34.
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Recently experts of the Israel police ballistic laboratory encountered a new version of the atypical firearms that is Airsoft pneumatic rifles converted for shooting cartridges of the caliber 5.56×45 mm. The Airsoft rifles are made to shoot nonmetal spherical projectiles in diameter of 6 mm. All variety Airsoft constructions can by divided into three groups: a) with spring mechanisms where the energy of compressed spring is used to produce air pressure; b) with electrical mechanisms where air pressure is provided by electrical pump; c) with mechanisms called Gas Blowback use energy of gas compressed in gas balloons. In many cases the Gas Blowback constructions of Airsoft rifle look similar to military firearms. They have similar construction of internal mechanisms. Different companies produce Airsoft copies of M-16 assault rifle. This Airsoft rifles can have the construction of trigger mechanism that is exact copy of the one used in M-16 assault rifle. Moreover, in some models detail sizes are the same as in real M-16 assault rifle. This makes possible to upgrade the Airsoft rifle for shooting cartridges of the caliber 5.56×45 mm by installing the rifled barrel (which can be bought on the Internet in USA) and using the original bolt carrier. The laboratory also received for the examination the upgraded Airsoft rifle samples with converted bolt carrier. So it made possible nоt use these firearm details. In some case identification of the evidence as atypical weapon is difficult because markings made by manufactures are identical to real M-16 assault rifles markings. This article discuses criminalistic examination methods of this homemade weapon type.
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Moss, Matthew. „The Benson–Poppenburg Breechloader“. Armax: The Journal of Contemporary Arms IX, Nr. 1 (31.07.2023): 67–76. http://dx.doi.org/10.52357/armax89653.
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The British Army’s search for a breech-loading rifle in the 1860s saw a variety of designs tested. The Benson–Poppenburg rifle, based on a system developed by a Prussian émigré engineer, is one of the most intriguing to have been rejected. Johann von der Poppenburg developed a simple breech action which did not require a bolt handle and could be used to retrofit existing muzzle-loaded rifles. Despite testing by both the British and Dutch armed forces, the rifle was never adopted for military service. In this short note, the author examines the rifle’s development, patents, mechanical characteristics, and trials history.
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Radovanović, Marko, Aleksandar Milić und Aleksandar Petrovski. „Analysis of accuracy and precision of shooting with home: Made automatic rifles using the AHP method“. Scientific Technical Review 71, Nr. 1 (2021): 30–37. http://dx.doi.org/10.5937/str2101030r.
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The paper presents the selection of the most accurate and precise automatic rifle, as a significant weapon primarily for the realization of combat tasks of the army. The size of the image of the scattering of shots and its distance from the target determine the degree of accuracy and precision of the automatic rifle. These indicators determine the probability of hitting, which affects the efficiency of solving fire tasks with an automatic rifle. The complexity of the problem is due to the different tactical and technical characteristics of automatic rifles and different shooting results. The paper presents and describes the results of shooting automatic rifles of domestic production, as follows: AR 7.62 mm M70 AB2, AR M21 5.56 mm, MAR M17 6.5 mm. Using the AHP method, the calculation of the weight coefficients of the criteria was performed. Using the AHP method, an analysis of the accuracy and precision of automatic rifle shooting was performed and a conclusion was made about the rifle that has the best results depending on the shooting distance. The obtained results enable the definition of proposals for equipping the Serbian Armed Forces units with an adequate automatic rifle.
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Szmit, Łukasz, Dawid Goździk und Adam Gawron. „TESTING THE HANDLES OF RAWAT FAMILY RIFLES FOR OPTIMISATION OF DESIGNS“. PROBLEMY TECHNIKI UZBROJENIA 153, Nr. 1 (03.07.2020): 7–20. http://dx.doi.org/10.5604/01.3001.0014.2695.
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Results of tests on ergonomics of the handles for RAWAT project rifles are presented in the paper. The use of the rifles in the past has brought many conclusions and comments concerning the rifle handles as well. In order to cope with the expectations of customers it was decided to modify the reloading grip, deflector of cases, trigger and the safety catch. These components were redesigned, and fabricated by 3D printing technology to be finally tested. The modified components were examined by testing the functionality and convenience of using. The tests contained the handling of the rifle and firing with live ammunition.
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Agyei, G., und J. J. Gordon. „Effect of Riffle Height and Spacing of a Sluice Board on Placer Gold Recovery“. Ghana Mining Journal 17, Nr. 1 (30.06.2017): 64–72. http://dx.doi.org/10.4314/gm.v17i1.7.
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Sluicing is the preferred mineral processing technique for the treatment of placer gold-bearing alluvium for small scale and artisanal miners in Ghana because sluice board is perceived to be the most cost effective device. However, there are differences in approaches from design to operation. In this work, about 50 kg of ore was obtained from “Peace School” small scale mining site near the University of Mines and Technology, Tarkwa. It was processed to determine the effects of riffle height and spacing on gold recovery. It was confirmed that, in order to trap a greater percentage of gold particles, the height of the riffle ought to be higher than the suspension height of the gold. The suspension heights of the gold particles of the various operational regimes of the sluice board at superficial velocities of 0.5 m/s, 1.0 m/s, 1.5 m/s and 2.0 m/ were 0.9 cm, 1.2 cm, 1.5 cm and 2.9 cm respectively. Analysis of concentrates showed that, 85.4% of gold was recovered during sluicing at approximately 1.0 cm riffle height. The lowest recovery was recorded at 0.5 cm riffle height. Gold recovery was also affected by riffles spacing. For the indicated speeds and the riffle heights the necessary spacing should not be more than 20 cm. The peak recovery was obtained at a riffle height of 1.0 cm but dropped after 20.0 cm spacing. Keywords: Sluice Board, Riffle Height, Gold, Rifle Spacing
7
Steiner, Kurt W. „The Ranger Rifle: An Alternative Firearm for Conservation Law Enforcement“. Armax: The Journal of Contemporary Arms VIII, Nr. 2 (31.01.2023): 55–72. http://dx.doi.org/10.52357/armax48057.
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Conservation Law Enforcement is one of the most dangerous jobs in the world, with more than a thousand Rangers killed over the last decade. Of these casualties, 58 per cent have been caused by either dangerous game or armed criminals. Despite this, it appears that only 29 per cent of Rangers worldwide carry out their duties while armed. In many instances, this is due to tight restrictions on the availability and issue of semi-automatic rifles. In countries where firearms laws restrict ready access to semi-automatic rifles, conservation agencies have often purchased and equipped their Rangers with shotguns. This article argues that, in the context of conservation law enforcement, shotguns have a range of limitations when compared to a bolt-action centrefire rifle, and that a civilian-legal ‘Ranger Rifle’—designed around law enforcement needs—is the best alternative where semi-automatic rifles are unavailable.
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Senturia, Yvonne D., Katherine Kaufer Christoffel und Mark Donovan. „Children's Household Exposure to Guns: A Pediatric Practice-Based Survey“. Pediatrics 93, Nr. 3 (01.03.1994): 469–75. http://dx.doi.org/10.1542/peds.93.3.469.
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Guns in the home are a factor in pediatric unintentional and intentional firearm injuries, yet the patterns of ownership and use are unclear. Objectives. To describe the prevalence of firearms in households containing children who go to pediatricians, the types of firearms owned, the purposes of such ownership, the conditions of firearm storage, and the social correlates of ownership. Methods. Survey of parents attending 29 (urban, suburban, and rural) pediatric practices in Chicago, New Jersey, Houston, Utah, Georgia, Iowa, and South Carolina for well or sick child care during a 1-week study period. The main outcome measure was ownership of rifle/shotgun and/or handgun. Results. Gun ownership was reported by 37% of 5233 respondent families: rifles (26%), handguns (17%), and powder firearm (32%). Ownership varied significantly across practices and geographical locations. Thirteen percent of 823 handguns and 1% of 1327 rifles were reported both unlocked and loaded. Recreation was the most common reason for both rifle (75%) and handgun (59%) ownership; 48% of handguns were kept for self-protection versus 21% of rifles. In logistic regression models, predictor variables for firearm ownership included rural area, single family dwelling, at least one adult male, and fewer preschool children (for handgun and rifle); mother with at least 12 years education (for handgun), and white mother (for rifle). Conclusions. The data presented suggest that US pediatricians routinely see children in families that own firearms, including a worrisome number that keep loaded and unlocked handguns. Until more detailed information becomes available, it is reasonable for pediatricians to be guided by these data, and so to counsel routinely about gun exposure.
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Soemardiawan, Soemardiawan, Nurdin Nurdin und Fitri Anggraeni. „The Effect of Imegery Training on Increasing Shooting Accuracy in the 10 m Air Rifle Women's Class Before Porprov XI in 2022“. JUPE : Jurnal Pendidikan Mandala 8, Nr. 3 (26.09.2023): 998. http://dx.doi.org/10.58258/jupe.v8i3.5955.
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The research problem is the low ability to shoot air rifles in Class 10 m Air Rifle Women athletes before PORPROV XI 2022, due to the still weak accuracy of the players. This is evident from the various tournaments that have taken part, very rarely athletes are able to shoot on target. Mental imagery is one of the mental exercises that really has an influence on improving performance, especially in shooting. The purpose of this study was to determine the effect of imagery training on increasing the accuracy of the 10 m Air Rifle Women Class before PORPROV XI 2022. The research design used was experimental one pre-test-post-test group, and the type of research is using experimental research. The research sample consisted of 9 athletes shooting the PERBAKIN NTB air rifle. The research instrument used was shooting 60 shots for 75 minutes. Based on data processing and analysis, the increase in the results of the initial training test was 73.33%. So the researchers concluded that: "There is an effect of imagery training on increasing the accuracy of the 10 m Class Air Rifle Women's shot before PORPROV XI 2022" meaning that there is a significant (real) effect of mental imagery training on the shooting skills of athletes shooting air rifles.
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Hung. „THE ANALYSIS OF THE MOTION OF BOLT CARRIER FOR THE AMPHIBIOUS RIFLES WHEN SHOOTING UNDERWATER IN THE INITIAL PERIOD“. Journal of Military Science and Technology, Nr. 67 (12.06.2020): 197–204. http://dx.doi.org/10.54939/1859-1043.j.mst.67.2020.197-204.
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The paper is focused on the establishment of a mathematical model describing the motion of bolt carrier for the amphibious rifles when shooting underwater in the period of the projectile moving to the position of the gas port. Besides, the conditions for bolt carrier motion are studied. The object of this paper is the bolt carrier assembly of the 5.56 mm amphibious rifle according to the designing of the research project of the ministry of defense 2017.73.034. The result of this research indicates that: for the 5.56 mm amphibious rifle, the bolt carrier is only moving when the velocity of the projectile at the position of the gas vent is larger 360.25 m/s. The result of this research can be applied to the dynamic analysis of the automatic mechanism of gas-operated rifles when shooting underwater.
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Nguyen Van Hung. „AN APPROACH METHOD FOR THE DYNAMIC ANALYSIS OF THE AMPHIBIOUS RIFLE WHEN SHOOTING UNDER-WATER“. Journal of Military Science and Technology, Nr. 66A (06.05.2020): 103–16. http://dx.doi.org/10.54939/1859-1043.j.mst.66a.2020.103-116.
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This paper focuses on establishing the dynamic model describing the motion of bolt-carrier for the amphibious rifles when shooting under-water. This dynamic model is applied for the 5.56 mm amphibious rifle designed by the research project of the ministry of defense. The model in this paper can be applied to study the influence of the structural parameters in rifles on the operation of the automatic system during shooting under-water and contributing to the adjustment, optimization designs.
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BAYINDIR, Abdullah. „Hanry Martiny Rifeles in The Army of The Ottoman Empire“. JOURNAL OF HISTORY AND FUTURE 8, Nr. 3 (30.09.2022): 859–85. http://dx.doi.org/10.21551/jhf.1176344.
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It is obvious that recently, the Ottoman empire has been working hard about the military reclamation, specially attached importance to infantry soldiers training. In that time the term’s conditions made it needful to modernise the army.It is known the sultan Abdülaziz (1886/1876) has critical efforts about that issue.in this context weapons that infantry soldiers used to have considered to change and was bought quite a number rifle from America. We can understand,the goverment had prefered the Henry-Martini’s rifles alongside nearly the similar the Winchester brand rifles. From 1872 the goverment has decided to buy from these brand’s rifles, The goverment has ordered rifles about 600,000 predominantly the brand of Hanry martini,and served hem to the army’s usage. In the war of Ottoman Empire Russia (93 war) has been observed the advantage of the rifles and the advantage in the army by the goverment. They paid attantion predominantly the use of the modern weapon traning In the military schools,soldiers practically learned about rifle,meintenance,pieces,repair and cleaning.the work we centre on is about the infantry soldiars during the in these years 1882-1893. A quite valuable information has been presented in the book was written by the Comte De Waldersee that named German executed who was a high ranked soldier.Among of these informations the usage stage of the weapons by the soldiers has been covered into visiually and with the details.The work evaluated from the ottoman turkish to the modern turkish by transcription.
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Radovanović, Marko, Aleksandar Petrovski, Elif Cirkin, Aner Behlić, Željko Jokić, Denis Chemezov, Elshan Giyas Hashimov, Mouhamed Bayane Bouraima und Chiranjibe Jana. „Application of the new hybrid model LMAW-G-EDAS multi-criteria decision-making when choosing an assault rifle for the needs of the army“. Journal of Decision Analytics and Intelligent Computing 4, Nr. 1 (21.01.2024): 16–31. http://dx.doi.org/10.31181/jdaic10021012024r.
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The paper addresses the selection of the most favorable alternative in the form of assault rifles to meet the requirements arising from modern combat operations. The complexity of the problem, conditioned by the different structural elements of automatic rifles and the specific situations of their use, has caused the application of Multi-Criteria Decision-making (MCDM) methods. A hybrid model was developed to guide the selection of the appropriate automatic rifle. The criteria were defined by experts, where the calculation of the weight coefficients of criteria was performed using the LMAW method Employing the grey EDAS method for MCDM, the study identifies an assault rifle that offers the most advantageous capabilities for carrying out firing tasks in the context of daily combat operations, with the aim of equipping the armed forces and raising the operational capability of the units. The validity of this model was verified through sensitivity analysis involving the adjustment of criteria weight coefficients.
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Aguirre-Puig, José Antonio, Vicente Javier Clemente-Suarez, Pedro Montañez-González und José Juan Robles-Pérez. „Efficacy of an Intense Rifle Fencing Training“. Open Sports Sciences Journal 7, Nr. 1 (24.01.2014): 60–64. http://dx.doi.org/10.2174/1875399x01407010060.
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The present study aimed to analyze the effectiveness of an intensive rifle fencing training based on a couple of the most effective fencing techniques compared to a traditional fencing training. 20 male professional soldiers of Spanish Army (28.6±2.4 years) were randomly divided in an experimental group (n: 10) and control group (n: 10). After 1 h rifle training sessions during 6 days, soldiers conducted simulated close quarter combats with rifles. Results showed that the experimental group obtained higher number of victories (17.0 vs. 7.0), number of techniques used (13.0 vs. 6.0), and had variations in body location of impact (head, trunk, legs and arms vs. head, trunk and arms) than control group. The experimental rifle fencing training focused on selected fencing techniques was more effective than the traditional rifle fencing training focused on a higher technical repertory.
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Michael, Danny. „Hunt Volitional Repeaters & Jennings Breechloaders: Tracing the Origins of the Lever-action Rifle“. Armax: The Journal of Contemporary Arms VII, Nr. 2 (2021): 1–16. http://dx.doi.org/10.52357/armax20674.
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This article explores the firearm designs that eventually led to the Henry and Winchester models of magazine-fed, lever-action rifles. As is so often the case in the history of firearms design, these two iconic rifles were not created ex nihilo, but were born from the cumulative efforts of many years of design work by different individuals. The impacts of the Henry and Winchester rifles on firearms development and military and frontier history are frequent topics of discussion, but the rifles’ predecessors are not nearly as well known. This is especially true with regard to the timeline of their development. Accordingly, this article examines the development history of the predecessors to the Winchester Model 1866, beginning in 1847 with inventors Walter Hunt and Lewis Jennings, and reviews the key design steps that resulted in one of the most iconic of American firearms: the lever-action repeating rifle.
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Gonzalez, Luís. „‘Mauser Japonés’ & ‘Remington Ruso’: A History of the Arisaka and Mosin–Nagant Rifles in the Mexican Revolution“. Armax: The Journal of Contemporary Arms VIII, Nr. 2 (31.01.2023): 1–24. http://dx.doi.org/10.52357/armax73331.
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During periods of arms scarcity, the Mexican army imported several different patterns of bolt-action rifles to address shortages and maintain firepower. During the Mexican Revolution (ca. 1910–1920), the Mexican Army—facing multiple domestic rebellions, European reluctance to supply weapons, and a U.S. arms embargo—turned to Japan to fill the growing gaps in its rifle inventory. Once the U.S. arms embargo was lifted, Mexico purchased numerous bolt-action rifles from the United States, including U.S.-produced Mosin–Nagant rifles. This article seeks to elaborate the historical background of these two unconventional and intriguing arms deals, and examines how a country engulfed in continuous civil wars managed to utilise the purchase and disposition of foreign surplus arms as part of its diplomatic agenda in the 1930s. The author presents a narrative of a twenty-year period of Mexican history as viewed through the histories of two obscure, yet important, rifles.
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Ferguson, Jonathan S. „Operational Trials of the E.M. 2 Automatic Rifle in Malaya, 1952–1953“. Armax: The Journal of Contemporary Arms VII, Nr. 1 (2021): 21–32. http://dx.doi.org/10.52357/armax80009.
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This article outlines the little-known field trials carried out with the British E.M. 2 advanced prototype assault rifle during the Malayan Emergency. It introduces the E.M. 2 rifle (accepted for service in 1951 as Rifle, 7 mm, No. 9, Mk. I) and the ‘Operational Trial’ as a part of the period British small arms procurement process. It then outlines the different trials carried out during the period in question and the military units involved, as well introducing some of the key personnel. Surviving examples of the E.M. 2 rifles used in these trials—today held in the Royal Armouries collection—are also identified and their known history elucidated. The implications for the ongoing development of the E.M. 2 after the trials period are then explored.
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Radovanović, Marko, Aleksandar Petrovski, Aner Behlić, Milica Perišić, Milan Samopjan und Bojan Lakanović. „Application model of MCDM for selection of automatic rifle“. Journal of Decision Analytics and Intelligent Computing 3, Nr. 1 (11.10.2023): 185–97. http://dx.doi.org/10.31181/jdaic10011102023r.
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The paper presents a selection of the best automatic rifle of domestic production. The complexity of the problem is conditioned by the different constructional characteristics of automatic rifles, which is why the application of multi-criteria decision-making methods is necessary. The choice of the most favorable alternative was made using the AHP - VIKOR method. By applying the AHP method, the calculation of the weight coefficients of the criteria was performed, while by applying the VIKOR method, the most favorable automatic rifle, was selected. The output is a proposal for the introduction into operational use and equipping of the security forces of the Republic of Serbia.
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Alexey, Isaev. „Soviet Anti-Tank Rifle RES: Invalid Design, Gone Epoch or Management System Failure?“ TECHNOLOGOS, Nr. 2 (2024): 83–93. http://dx.doi.org/10.15593/perm.kipf/2023.2.07.
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The article is dedicated to one of the rare exhibits of the Museum of Domestic Military History: experimental 20-mm anti-tank rifle RES which had been designed and tested for the Red Army during the Great Patriotic War. Development, testing, and introduction to military service of this anti-tank rifle is a good sample of decision making in the Soviet State military management system. The task of research is to formulate a scientific answer to the question about the causes of delays in launching mass-production of a high-performance anti-tank rifle RES despite the Red Army infantry urgent needs for an effective anti-tank weapon. There are some hard-toexplain delays in the RES life-cycle that prevented its transition from army testing to massproduction. Teething problems of the RES were the same as in case of the mass-produced PTRD and PTRS. Insufficient armor-piercing capabilities of the PTRD and PTRS were clear for the Main Artillery Directorate that was responsible for anti-tank rifles in the Red Army. Despite the interest of high-ranking and well-known as a soviet repressive machine leader L.P. Beria in the RES project, until the war ended the high-performance rifles did not reach the battlefields. The article describes a few factors that influenced decision making. The first one is bureaucratic delays due to the Main Artillery Directorate desire to follow the prescribed weapon life-cycle procedures after the 1941 crisis was over. The second one is objective factors connected to armor protection development of German tanks. German engineers' and military leaders’ steps to increase tanks and self-propelled guns armor-protection were really effective in view of anti-tank rifles performance. The third influence is the presence in the USSR of alternative anti-tank weapon projects by other engineering teams. The research is based on a wide range of documents.
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Baird, Justin. „The Danish Gevær M/1889: A Developmental History of the Krag–Jørgensen Rifle in Denmark“. Armax: The Journal of Contemporary Arms VII, Nr. 2 (2021): 57–86. http://dx.doi.org/10.52357/armax21011.
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The Krag–Jørgensen rifle is perhaps best known in the Anglosphere for the important role it played in shaping America’s modern military, ushering the country into the era of smokeless powder and magazine-fed, repeating firearms at the end of the 19th century. Although several books have been written on the American Krag–Jørgensen models, very little has been written in English on their Scandinavian counterparts. The Krag–Jørgensen rifle, although developed in Norway, was first adopted in Denmark as the Gevær M/1889. The lack of reliable scholarship examining Scandinavian rifles of this period has given rise to a range of false narratives and misinformation connected with the early development of the rifle and its adoption by the Danish armed forces. This article seeks to address these issues head-on, providing a verifiable—if general—narrative of the early development of the weapon and its early trials and adoption.
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Delucchi, Carla M. „Comparison of community structure among streams with different temporal flow regimes“. Canadian Journal of Zoology 66, Nr. 3 (01.03.1988): 579–86. http://dx.doi.org/10.1139/z88-085.
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A study was conducted in four streams in the same watershed in New York to determine whether the benthic invertebrate community structure varied among streams with different temporal flow regimes. Timed kick samples were taken from 13 riffles and 4 pools once a month from June to November 1982. Riffle sites were classified according to temporal flow regime as permanent, intermittent (dry for less than 3 months), or dry (dry for over 3 months), and varied in size as a function of discharge. Ordination analysis (detrended correspondence analysis) showed that the structure of the benthic invertebrate communities in these streams was related not only to riffle permanence, but also to other abiotic and biotic parameters. Differences in community structure were greater between adjacent pools and riffles than between temporary and permanent riffles. Stream size, seasonal changes in taxa, how recently the riffle had dried, and the length of the dry period contributed to differences in community structure among riffles. It appears that differences in community structure between permanent and temporary riffles are minimized by generalized adaptations of stream benthos, such as high rates of migration, drought-resistant eggs, and the tendency to take refuge in the hyporheic zone.
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WOŹNIAK, Ryszard B., Mirosław ZAHOR, Paweł MADEJ, Janusz PAWLAK und Norbert PIECHOTA. „Evolution of the MSBS Grot Assault Rifle from Version A0 to Version A2“. Problems of Mechatronics Armament Aviation Safety Engineering 12, Nr. 1 (31.03.2021): 75–86. http://dx.doi.org/10.5604/01.3001.0014.7852.
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On 15 December 2017, Fabryka Broni “Łucznik”-Radom Sp. z o.o. (FB Radom), a subsidiary of Polska Grupa Zbrojeniowa S.A., delivered the first batch of 1,000 MSBS Grot C 16 FB M1 calibre 5.56 mm standard (basic) assault rifles (version A0) to the Polish Territorial Defence Force and thus initiated the process of deployment of the assault rifle in the Polish Armed Forces. MSBS Grot was developed by Polish design and process engineers at FB Radom and the Military University of Technology (MUT, Warsaw, Poland) who by mediation of the proper Armament Acquisition and Development Department collected the improvement suggestions and operational feedback from 2.5 years of testing by operators from the armed forces. The suggestions and feedback were thoroughly analysed and discussed during periodic meetings attended by the representatives of the Territorial Defence Force (TDF) Command, the Special Forces Component Command, the 3rd Regional Military Representation (RMR), MUT, and FB Radom. Based on the conclusions from the testing period and the results of theoretical and instrumental testing of the solutions proposed for implementation, the MSBS Grot assault rifles show systematic improvements up to the current version, A2. This paper presents the design of the MSBS Grot Version A0 assault rifle and the construction and processing modifications for version A1 and version A2. During the optimisation effort backed by theoretical and instrumental testing, there was special focus on the assurance of high operating safety and reliability, plus the required ergonomics of the assault rifle under various operating conditions. The paper also presents the avenues for further potential improvements of MSBS Grot.
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Lonzarich, D. G., M. R. Lonzarich und M. L. Warren Jr. „Effects of riffle length on the short-term movement of fishes among stream pools“. Canadian Journal of Fisheries and Aquatic Sciences 57, Nr. 7 (01.07.2000): 1508–14. http://dx.doi.org/10.1139/f00-082.
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Recent research has suggested that the within-habitat dynamics of fish populations and assemblages can be affected by the spatial distribution of habitats within streams. In this study, we determined the extent to which pool isolation (length of riffles connecting adjacent pools) influenced fish movement in two Arkansas streams. We marked individuals from 12 pools assigned to two treatment categories: pools separated by long riffles (>50 m) and those separated by short riffles (<10 m). Repeatedly snorkeling pools for 3 days in 1995 and 1997, we discovered substantial emigration (>20%) and significant effects of riffle length. Total emigration from short-riffle pools was three times higher (29%) than movement from long-riffle pools (10%). Further, marked fish in short-riffle pools moved upstream and downstream with equal frequency, whereas fish in long-riffle pools moved twice as often downstream. Collectively, these results indicate significant effects of habitat spacing on short-term movement patterns by fish. In streams, where fish are distributed within a mosaic of habitats of varying quality, such movements may allow individuals to assess spatial variability in resource conditions (e.g., food, predators). Because land-use activities can alter habitat spacing, these findings have important implications for fish conservation in degraded streams.
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Moledina, Zahra, Kiran Singh und Angela Tewari. „Poster presentationsCD10 Gunpowder dermatitis: is there such a thing?“ British Journal of Dermatology 191, Supplement_1 (28.06.2024): i92. http://dx.doi.org/10.1093/bjd/ljae090.189.
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Abstract We report a case of a 17-year-old boy who developed a facial rash on three consecutive occasions after firing a rifle. Patch testing to the British Standard Series was positive to cobalt chloride. Our patient described a clear history of the gun smoking and then him developing an itchy facial rash 2 h later. Over the next few hours, he developed worsening facial erythema and swelling. This was treated with antihistamines and topical steroids and resolved. A few months later, he developed a similar rash with facial oedema when firing his rifle. After just under 2 h there was facial erythema and oedema, and erythematous papules could be seen on the wrists. This was again treated in a similar manner and resolved. There was no oral or laryngeal involvement. Moreover, a third time, when he was cleaning his rifle, he developed a similar rash a few hours later. There have been no episodes of the rash occurring outside of relation to the rifle. It was felt that this could represent a contact allergy to the potassium nitrate found in gunpowder that would rebound back from the butt of the rifle to enable bullets to be fired from the cartridge. Our patient used blanks, which also contain gunpowder but without the firing bullets. The patient was tested to the European Standard Battery only. At day 4, the patient developed a 2++ reaction to cobalt only. Cobalt chloride is a common metal known to cause a delayed hypersensitivity reaction, affecting approximately 1–3% of the population (Midander K, Werner P, Isaksson M et al. Cobalt nanoparticles cause allergic contact dermatitis in humans. Br J Dermatol 2023; 188: 278–87). It is used to line the barrel of some rifles to reduce erosion and barrel wear (De Rosset WS, Montgomery JS. Cobalt-base alloy gun barrel study. Wear 2014; 316: 119–23). It is thought that our patient experienced immediate contact urticaria with a secondary id reaction to the cobalt. We have counselled him on other cobalt-containing products. There are currently no published reports of hypersensitivity reactions to cobalt through the use bullet-containing rifles.
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Peek, Kevin, und Benjamin Black. „Children’s toys no longer: a porcine model study of the lethality of modern air rifles“. New Zealand Medical Journal 137, Nr. 1591 (08.03.2024): 55–61. http://dx.doi.org/10.26635/6965.6378.
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aims: We observed modern spring-loaded air rifles reaching velocities similar to small-bore rifles, raising concerns about their potential lethality. After encountering two life-threatening thoracic injuries in our practice, we conducted a study to assess the injuries that a commonly available air rifle could cause in a porcine cadaver model. methods: We conducted shooting experiments from 5 and 10 metres away using a .22 calibre spring-loaded airgun, firing five shots into the anterolateral chest on the left side at both distances. Additionally, we repeated the experiment with ten shots into 10% ballistics gel behind an explanted chest wall to evaluate chest wall penetration reliability. results: Out of the ten combined shots, six resulted in lethal or potentially lethal injuries, including multiple cardiac injuries. Moreover, we observed chest wall penetration in 9 out of 10 shots, with an average penetration depth of 106mm. Non-life-threatening injuries appeared to be influenced by shot location rather than an inability to penetrate the chest wall. conclusion: Our study raises significant concerns about the potential lethality of unrestricted air rifles in New Zealand. With muzzle velocities comparable to small-bore rifles, these firearms should be reconsidered in terms of regulation and possibly restricted to gun license holders.
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Oen, E. O., und S. K. Knudsen. „Euthanasia of whales: the effect of .375 and .485 calibre roundnosed, full metal-jacketed rifle bullets on the central nervous system of the common minke whale“. J. Cetacean Res. Manage. 9, Nr. 1 (22.02.2023): 81–88. http://dx.doi.org/10.47536/jcrm.v9i1.695.
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The effect of rifle projectiles used for the euthanasia of stranded or hunted whales has been an issue for debate, in particular in the International Whaling Commission (IWC) and the North Atlantic Marine Mammal Commission (NAMMCO). In the Norwegian hunt for common minke whales, 9.3mm, .375 or .458 calibre rifles are used as backup weapons to euthanise whales that are not deemed dead after being hit with a harpoon grenade. When using the rifle, the hunters aim at the brain of the animal. The present study investigates the effects of the two rifle calibres .375 and .458 and round nosed, full-metal jacketed bullets in 29 common minke whales. The whales were examined post mortem shipboard and 22 of the brains were fixed in situ and later subjected to gross and light microscopic examination. The results show that the two types of bullets are fully capable of penetrating the skull and spinal bones of common minke whales and fatally damaging the central nervous system, resulting in immediate or very rapid loss of consciousness.
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Bordyian, P. „RECOMMENDATIONS FOR INCREASING THE EFFICIENCY OF SNIPER WEAPON FIRE BY ADJUSTING EXISTING AND COMPILING NEW FIRING TABLES“. Collection of scientific works of Odesa Military Academy, Nr. 17 (31.08.2022): 101–9. http://dx.doi.org/10.37129/2313-7509.2022.17.101-109.
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The article examines the use of sniper weapons in the Armed Forces, both outdated and modern, domestically produced and provided by Ukraine's allied states as military aid. Some features of the construction of sniper weapons and their characteristics are considered. Evaluation of the effectiveness of firing from various weapons is carried out using so-called fire efficiency indicators. Based on them, the possible level of damage to various typical targets is calculated, on the basis of which firing rules are developed. The range of effective fire is understood as the maximum range at which a given level of target defeat is achieved with a rational consumption of ammunition and firing time. It is necessary to understand that the range of effective fire of a weapon is not a constant value, the same for all conditions. It is impossible to remember all cases of the range of effective fire from different targets, from different positions, with different ammunition. It is enough to understand and remember only the typical variants of the conditions of firing with this weapon and the corresponding ranges of effective fire. And use them to solve the problem in specific conditions. the range of effective fire from it depends on specific conditions. Some answers to the evaluation of the effectiveness of fire from the SGD army sniper rifle are given by the Tables of shooting at ground targets with small arms of 5.45 and 7.62 mm caliber. However, the effect of these Tables does not extend to the latest samples of domestic production and provided to Ukraine by Western partners. That is why suggestions and recommendations have been developed for correcting existing and compiling similar shooting tables for modern sniper rifles. Keywords: small arms, sniper rifle, large-caliber sniper rifle - rifles for defeating material means, ammunition, firing tables, firing efficiency.
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Naman, Sean M., Jordan S. Rosenfeld, Laura C. Third und John S. Richardson. „Habitat-specific production of aquatic and terrestrial invertebrate drift in small forest streams: implications for drift-feeding fish“. Canadian Journal of Fisheries and Aquatic Sciences 74, Nr. 8 (August 2017): 1208–17. http://dx.doi.org/10.1139/cjfas-2016-0406.
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The influence of stream channel structure on the production of prey for drift-feeding fish is not well understood. We quantified drift production, the entry rate per streambed area, and drift flux, the total export rate per channel unit, in three second-order, forested streams in southwest British Columbia, Canada. We tested whether (1) drift production was higher in riffles than in pools, (2) drift flux increased with riffle length, and (3) prey body size was larger from riffles relative to pools and from terrestrial drop relative to aquatic drift. Total and aquatic-derived drift production (mg·m−2·h−1) was ∼3.5 times higher in riffles relative to pools; however, terrestrial drift did not differ between channel types. Total drift flux (mg·h−1) was positively related to riffle length. Terrestrial invertebrates were approximately three times larger than aquatics, and invertebrates from riffles were approximately three times larger on average than those from pools. These results suggest that channel structure directly affects prey availability and prey quality for drift-feeding fish and that long riffles may be key areas of prey generation.
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Phillips, Patrick. „“The Missing Mum Mystery”: Solved“. Armax: The Journal of Contemporary Arms IX, Nr. 2 (31.12.2023): 43–58. http://dx.doi.org/10.52357/armax10409.
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For decades, collectors and museum curators have pondered the meaning behind the defacing or removal of Imperial chrysanthemum seals on Japanese rifles following the surrender of Japan in 1945. Several myths and explanations for the removal are commonplace and have been perpetuated since the end of the Second World War, but definitive evidence explaining exactly why the chrysanthemum was removed has not been presented in the English language until recently. The truth of the matter lies with the disarmament of Japan, Japanese ordnance regulations, and perceived requirement of removal by American servicemembers. All Japanese rifles since the 1880s were marked with the chrysanthemum, and it is common to find examples of various models of rifle with the chrysanthemum intact, whilst other examples of the same model have had the seal removed or mutilated. This article presents evidence which proves that the Japanese did indeed order the removal of the Imperial chrysanthemum and that this had been an established practice decades before the Second World War.
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Fox, NC, N. Blay, AG Greenwood, D. Wise und E. Potapov. „Wounding rates in shooting foxes (Vulpes vulpes)“. Animal Welfare 14, Nr. 2 (Mai 2005): 93–102. http://dx.doi.org/10.1017/s0962728600029080.
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AbstractOne-hundred-and-ninety-nine shooters in England, Wales and Scotland shot at fox-shaped targets in 35 shotgun regimes including .410 and 12 bore using No 6, BB or AAA shot sizes at 25, 40 or 60 yards, with open and full choke barrels, and skilled, semi-skilled or unskilled shooters. A further 16 regimes used rimfire rifles at 50 yards (both supported using a gun rest and unsupported) and centrefire rifles at 100 and 150 yards, by day and by night. The targets were life-sized paper foxes, traced from a longitudinal section of a real fox and mapped with the internal anatomy. For shotgun trials, the targets were moved across a gap, allowing the shooters 3 or 3.5 s to take aim and fire. For rifle trials, the static targets were raised up for 4 s and then lowered. Fifteen dead foxes, shot with the same ammunition, ranges and angle as in the shooting regimes, were assessed for internal injuries caused by each regime. Ammunition was tested in comparative card-penetration tests. A total of 1085 shotgun shots and 885 rifle shots at the targets were scored as ‘killed’, ‘seriously wounded’, ‘lightly wounded’ or ‘missed’. As shooters' skill level increased, the ‘kill’ rate increased, the ‘miss’ rate decreased but the ‘wounding’ rates stayed much the same. No 6 shot ‘wounded’ because of poor penetration. AAA had poor pattern density at ranges beyond 40 yards. At ranges of up to 40 yards, both AAA and BB shot performed well, BB being the optimum. .410 shotguns with No 6 shot ‘wounded’ but seldom ‘killed’. Rifles ‘killed’ better than shotguns and ‘wounded’ less. There was no regime that had no probability of ‘wounding’; however, the latter varied dramatically across the trials with different types of gun, ammunition and shooters' skill level. Mitigating factors such as the use of second shots or dogs are discussed.
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Robson, BJ. „Small spate disturbance and the complexity of habitat architecture in Mountain River, Tasmania“. Marine and Freshwater Research 47, Nr. 6 (1996): 851. http://dx.doi.org/10.1071/mf9960851.
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Densities of benthic invertebrates were counted over several weeks before and after a small winter spate (15.5 times base flow) in two riffle types of contrasting architectural complexity in Mountain River, Tasmania. Complex benthic architecture reduced the impact of this spate on invertebrate densities over the short term (seven days). Longer-term recovery (several weeks) was unaffected by riffle architecture, with one of the riffles recovering much more slowly than the others. Refuges from small spates in Mountain River may exist in mid channel in complex boulder-cobble riffles. Within its temporal context, the effects of the spate on the study sites were of a similar magnitude to other unexplained population fluctuations.
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Thompson, Douglas Marshall. „The velocity-reversal hypothesis revisited“. Progress in Physical Geography: Earth and Environment 35, Nr. 1 (15.07.2010): 123–32. http://dx.doi.org/10.1177/0309133310369921.
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In 1971, Edward Keller proposed the velocity-reversal hypothesis to describe observations where near-bed velocities in pools increased at a faster rate than in riffles. The reversal in conditions was used to explain the maintenance of pool-riffle sequences. The hypothesis continues to draw interest, and research shows that velocity reversals occur in limited conditions, but average cross-sectional velocities in pools do not universally exceed those in riffles at near-bankfull flows. A consensus is now beginning to form that flow convergence in pools is common at high flow and helps to form an isolated region of jet flow with high velocities that maintains the characteristics of the pool-riffle sequence.
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Ahmad, Faiz MH, S. K. Nanda, S. R und D. S. Grewal. „Rifled carotid: Internal carotid artery thrombosis from prolonged carrying of a military rifle“. Journal of the Royal Army Medical Corps 165, Nr. 6 (27.05.2019): e2-e2. http://dx.doi.org/10.1136/jramc-2019-001225.
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BackgroundTraumatic carotid artery thrombosis is uncommon and it usually results from penetrating injuries and less commonly secondary to blunt trauma. It can lead to delayed clinical presentation, which leads to delay in the diagnosis. Soldiers in combat scenario also can present with such an illness, which results from varied modes of injuries. Our case illustrates an unusual cause of carotid thrombosis.Case presentationOur patient is a 37-year-old soldier who developed neck pain and headache following a 5 km training run with rifle on the shoulder and subsequently developed left upper limb weakness and evaluation revealed extracranial right internal carotid thrombosis. He was managed with anticoagulants and antiplatelets with complete resolution of the thrombosis and complete recovery of the weakness.ConclusionBlunt trauma to the neck in the form of carrying a rifle for a prolonged duration can result in injury to the carotid vessels leading to delayed neurological presentation. Educating the troops regarding such a mode of illness will prevent such a catastrophic nature of vascular injury resulting in ischaemic stroke.
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Summerfield, P. H. „Small Arms Manufacturing for the 1990s“. Proceedings of the Institution of Mechanical Engineers, Part B: Journal of Engineering Manufacture 203, Nr. 2 (Mai 1989): 75–82. http://dx.doi.org/10.1243/pime_proc_1989_203_052_02.
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When British Aerospace acquired Royal Ordnance in 1987 it was midway through the first phase of a fixed-price contract to supply rifles to the Ministry of Defence (MOD), its single biggest customer, and had a firm option on the second phase. However, there was a significant problem in that each new British Army rifle was incurring a 30 per cent loss and deliveries were 18 months behind programme. The new management team had two months to decide whether to accept the option or pull out. After that the MOD would go to competitive tender. The decision was a fundamental one for Royal Ordnance. To pull out of the contract would mean in effect surrendering the rifle business to competitors, but if the contract was accepted it was clear that radical changes would be required to cut costs and reverse the losses. The management team chose to stay in the market and fight. The events that followed, which are described in this paper, illustrate the step function in change that successful companies are having to make to stay ahead of the competition.
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Burns, Mike. „Sterling & Enfield Conversions of Lee–Enfield No. 4 Rifles to 7.62 NATO: An Explanation for Certain Design Choices?“ Armax: The Journal of Contemporary Arms IX, Nr. 1 (31.07.2023): 77–88. http://dx.doi.org/10.52357/armax64815.
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Both the Sterling Engineering Company Limited and Royal Small Arms Factory Enfield proposed conversions of Lee–Enfield No. 4 rifles to the 7.62 × 51 mm (NATO) calibre in the 1960s. This article discusses a number of the design details of these two distinct conversions, and posits a possible explanation for some of the differences, namely on the basis of Sterling’s UK Patent No. 897,079. By making certain design choices regarding the charger bridge and ejector, Enfield managed to find a technical solution which avoided infringing Sterling’s patent, and hence avoided a legal battle that could have arisen from its 7.62 × 51 mm No. 4 rifle conversions.
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Guo, J. H., H. Zhang und X. D. Zhang. „Effect of Rifling Height on Convective Heat Transfer Flux and Erosion for Cannon Barrel“. Journal of Physics: Conference Series 2460, Nr. 1 (01.04.2023): 012109. http://dx.doi.org/10.1088/1742-6596/2460/1/012109.
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Abstract The effect of rifling height on erosion for cannon barrel was studied in this paper. An erosion velocity kernel function which is an Arrhenius type function revealing thermal and chemical effects is proposed. The erosion function is employed in numerical simulations to obtain the erosion depth after several rounds for two kinds of gun barrels at commencement of full rifling. By comparing final erosion depths obtained by numerical simulations and firing tests, it can be concluded that heat transfer flux between propellant gas and barrel with different rifles are absolutely different. Then the effect of rifle height on convective heat transfer flux is discussed in this paper.
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Burns, MS, Amy R., Susan 'BOON' Murray, EdD, CCLS, CTRS und Dennis C. W. Fater, PhD, PT, Cert MDT. „Designing and implementing a rifle shooting clinic as leisure skill development for adults with physical disabilities“. American Journal of Recreation Therapy 12, Nr. 3 (01.07.2013): 34–48. http://dx.doi.org/10.5055/ajrt.2013.0051.
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Backgroun/rationale: Adults with physical disabilities are an underserved population among Americans who participate in adaptive shooting sports. A basic rifle marksmanship clinic has potential to promote a low impact outdoor physical activity for adults with physical disabilities as leisure skill development.Methods: This grant-funded service project of a therapeutic recreation (TR) graduate student utilized program design and evaluation. The specific program design included best practices for teaching basic rifle marksmanship and measured participants’ performance outcomes related to shooting skills and knowledge. A half-day rifle marksmanship clinic was conducted as a university-funded community service grant which provided rifle instructor certification, ammunition and supplies. The clinic was a collaboration between physical therapy (PT) and TR faculty and PT, OT, and TR majors.Results: All participants gained shooting knowledge and skill through this program. A shooting clinic format with classroom instruction followed by practice on a live firing range was effective. The use of a leisure partner for each participant helped sustain interest and continued support to develop skill after the clinic. Doing an in-home exercise program prior to the clinic reduced muscle soreness from the intensity of target practice in a clinic format.Conclusions: TR specialists may promote shooting sports as treatment for functional improvement or as leisure skill development. They may collaborate with physical and occupational therapy to emphasize psychosocial aspects of shooting sports.Recommendations: Shooting skills instructors could expand live fire training time at clinics, start training with virtual shooting or air or laser rifles to assess participant readiness, promote inclusive practice specific to shooting sports, and apply empowerment evaluation as a signature program strategy.
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Herleth-King, Shawna S., Hayden T. Mattingly und Robert J. DiStefano. „Habitat use of Orconectes meeki meeki and Orconectes williamsi in an intermittent Ozark stream“. Freshwater Crayfish 21, Nr. 1 (31.12.2015): 103–14. http://dx.doi.org/10.5869/fc.2015.v21-1.103.
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Abstract Relatively few studies have examined fine-scale habitat use of crayfish in headwater streams, despite increasing awareness of the importance of such habitats. Orconectes meeki meeki, Meek’s crayfish, is endemic to the upper White River drainage of Missouri and Arkansas, and Orconectes williamsi, Williams’ crayfish, occurs only there and in the Arkansas River drainage. Our objective was to describe speciesspecific habitat use of these crayfishes at two spatial scales (pool-riffle and microhabitat) within a seasonally intermittent stream. From May through August 2008, we sampled ten riffles and five pools in Rock Creek, Missouri, to quantify surface and hyporheic environmental variables. Density of O. m. meeki was similar between riffles and pools; O. williamsi density was greater in riffles. At the riffle scale, O. m. meeki was positively associated with wetted channel width and upwelling hyporheic zones; O. williamsi was negatively associated with surface and hyporheic water temperatures. At the microhabitat scale within riffles, O. m. meeki was positively associated with wetted depth and pebble-cobble substrates; O. williamsi was positively associated with surface velocity and pebble-cobble substrates. Habitat use was relatively static for both species as surface flows waned from May through August. Our research provides detailed, fine-scale habitat associations of the crayfish to complement existing knowledge of these species at coarser spatial scales.
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Sanchez, Dana M., Clinton W. Epps und David S. Taylor. „Estimating Lead Fragmentation from Ammunition for Muzzleloading and Black Powder Cartridge Rifles“. Journal of Fish and Wildlife Management 7, Nr. 2 (01.09.2016): 467–79. http://dx.doi.org/10.3996/092015-jfwm-086.
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Abstract Lead bullet fragments pose a health risk to scavengers and hunters consuming game meat, but lead or lead-core bullets are still commonly employed for big and small game hunting. Bullet fragmentation has been assessed for modern, high-velocity rifles, but has not been well documented for black-powder cartridge rifles or muzzleloading firearms. We used two established methods to estimate bullet fragmentation. We evaluated a traditional .54 round ball and a modern-designed .54 conical bullet for muzzleloaders, two types of .45-70 black powder rifle cartridges, and a modern lead-core high-velocity bullet (.30-06) as our comparison control. We tested penetration and fragmentation in water (n = 12) and ballistics gel (n = 2) for each bullet type. We measured lead mass lost to fragmentation and x-rayed ballistic gels to visualize fragmentation patterns. The modern .30-06 bullets we tested (Remington Core-Lokt) retained a mean of only 57.5% of original mass, whereas mean retention by muzzleloader and black powder cartridge bullets ranged 87.8-99.7%. Round balls and .45-70 bullets shed less lead (i.e., 0.04g and 0.19g on average respectively) than the modern conical .54 muzzleloading bullets (3.08g) or the .30-06 control (4.14g). Fragments from round balls and black powder cartridge bullets showed far less lateral spread compared to the high-velocity modern bullet. Our findings suggest that round balls for muzzleloaders and black powder cartridge bullets may leave far fewer lead fragments in game than the conical muzzleloader bullet or modern high-velocity rifle bullet we tested, and thus could pose a lower risk of secondary lead poisoning for humans and wildlife. Artificial tests cannot replicate conditions encountered in the field, but the striking differences we observed in bullet fragmentation even under severe testing conditions suggests that follow-up tests on game animals may be warranted.
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Mather, Martha E., und Roy A. Stein. „Using Growth/Mortality Trade-offs to Explore a Crayfish Species Replacement in Stream Riffles and Pools“. Canadian Journal of Fisheries and Aquatic Sciences 50, Nr. 1 (01.01.1993): 88–96. http://dx.doi.org/10.1139/f93-011.
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A crayfish species replacement is underway in Ohio streams. We explore how growth, mortality, habitat use, and size influence the replacement of Orconectes sanborni by O. rusticus. In field cages we assessed growth of crayfish. Both species grew faster when confined to riffles and O. rusticus grew faster than O. sanborni in this fast-water habitat. In another experiment, we tethered crayfish in riffles, shallow pools (< 40 cm), and deep pools (> 40 cm) to assess mortality. After 8 d, more crayfish were eaten in deep pools than in riffles or shallow pools. Given this finding, we predicted that crayfish should preferentially occupy high-growth low-mortality riffles. To test this hypothesis, we quantified crayfish habitat use in sympatric streams, with and without fish predators. Crayfish did not prefer riffles. Apparently, juvenile crayfish do not assess specific benefits and costs using only food and fish predators. Other costs associated with riffles (e.g. passive drift, terrestrial predators, summer desiccation, physiological cost of position maintenance, etc.) must reduce riffle use. In addition, O. rusticus grows larger than O. sanborni. Because size confers advantages in biotic interactions, this critical finding may be the key to the replacement.
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Hampton, Jordan O., Mark Laidlaw, Eric Buenz und Jon M. Arnemo. „Heads in the sand: public health and ecological risks of lead-based bullets for wildlife shooting in Australia“. Wildlife Research 45, Nr. 4 (2018): 287. http://dx.doi.org/10.1071/wr17180.
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Lead (Pb) is a toxic element banned from fuel, paint and many other products in most developed countries. Nonetheless, it is still widely used in ammunition, including rifle bullets, and Pb-based bullets are almost universally used in Australia. For decades, poisoning from Pb shot (shotguns) has been recognised as a cause of disease in waterfowl and Pb shot has been subsequently banned for waterfowl hunting in many jurisdictions. However, the risks posed by Pb-based bullets (rifles) have not been similarly recognised in Australia. Pb-based rifle bullets frequently fragment, contaminating the tissue of shot animals. Consuming this Pb-contaminated tissue risks harmful Pb exposure and, thus, the health of wildlife scavengers (carrion eaters) and humans and their companion animals who consume harvested meat (game eaters). In Europe, North America and elsewhere, the environmental and human health risks of Pb-based bullets are widely recognised, and non-toxic alternatives (e.g. copper-based bullets) are increasingly being used. However, Australia has no comparable research despite widespread use of shooting, common scavenging by potentially susceptible wildlife species, and people regularly consuming shot meat. We conclude that Australia has its collective ‘head in the sand’ on this pressing worldwide One Health issue. We present the need for urgent research into this field in Australia.
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Сhernykh, О. N. „Assessment of the stage of sediment movement under the action of wave flow on the elements of the channel of a water body in the agro-industrial complex“. Prirodoobustrojstvo, Nr. 2 (2024): 57–62. http://dx.doi.org/10.26897/1997-6011-2024-2-57-62.
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The purpose of the work is to determine, in laboratory conditions, the magnitude and laws of distribution of bottom wave flow velocities, at which various stages of particle movement and riffle formation occur in the area of beach slopes of water bodies of the agro-industrial complex. The results of studies of velocities characterizing the regimes of sediment movement in a wave flow acting on loose slopes and bottom areas of the shallow zone of reservoirs and streams are presented. The influence of artificial flow turbulization on characteristic flow speeds, including wave speed on the parameters of bottom riffles, is considered. An analysis of the influence of artificial turbulization on the speed of sediment movement is given and recommendations are given for determining the non-erosive speed of the wave flow in its absence. A dependence is presented for determining the height of the riffles. It has been established that the velocities on the riffle crest increase by no more than 1.7 times compared to the speed on the flat bottom of the near-shore zone of a large water body.
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Goździk, Dawid, Jacek Kijewski, Przemysław Kupidura und Łukasz Szmit. „THE INFLUENCE OF THE MUZZLE DEVICE ON THE SPREAD AND THE JUMP OF SELECTED RIFLES OF THE MODULAR SMALL ARMS SYSTEM MSBS-5,56“. PROBLEMY TECHNIKI UZBROJENIA 150, Nr. 2 (22.11.2019): 45–57. http://dx.doi.org/10.5604/01.3001.0013.5896.
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Results of tests, carried out so far for MSBS system rifles, have shown a large impact of muzzle devices on spread of shots pattern. In order to select the optimal design of the muzzle device, a series of firings were carried out, primarily with a light machine gun and a sniper rifle. It was assumed that a weapon jump, which is also the most easily measurable parameter, is the main factor affecting the shot pattern at precision firings. The jump parameters were determined by using a unique laboratory stand that allows measurement in conditions as close as possible to the real ones. Measurements of barrel movement were also made for selected designs with a high speed camera. The results of laboratory tests were verified by shootings on the range.
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Natsumeda, Takaharu, und Kei’ichiro Iguchi. „Habitat-specific effects of interstitial space between stream substrate particles on the colonization of aquatic organisms“. International Aquatic Research 11, Nr. 4 (05.11.2019): 347–58. http://dx.doi.org/10.1007/s40071-019-00243-1.
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Abstract We examined the effects of interstitial space between stream substrate particles on the colonization of aquatic organisms using three types of substrates (gravel, a cobble, and a cobble on gravel) in a riffle and pool of a temperate stream. Significantly greater abundance, wet weight, diversity (H′), taxonomic richness, and evenness of aquatic organisms were found in the riffle than in the pool, and the interstitial space substrate (i.e., a cobble on gravel) had significantly greater abundance, wet weight, and taxonomic richness of aquatic organisms than did the cobble substrate. Of the 13 families observed in the experiments, larval net-spinning caddisfly (Hydropsychidae) dominated the riffle in terms of the abundance and wet weight; chironomid larvae dominated both the riffle and the pool in terms of abundance. Simple main effect tests indicated significant effects of substrate on the abundance and wet weight of larval caddisfly in the riffle, and post hoc tests on substrate in each habitat indicated that the abundance and wet weight of larval caddisfly on interstitial space substrate were significantly greater than those on cobble substrate in the riffle. Our results suggest the importance of interstitial space between stream substrates in riffles to ensure higher colonization rates of aquatic organisms such as larval net-spinning caddisflies characterized as filter feeders.
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Bult, Tammo P., Stephen C. Riley, Richard L. Haedrich, R. John Gibson und Jan Heggenes. „Density-dependent habitat selection by juvenile Atlantic salmon (Salmo salar) in experimental riverine habitats“. Canadian Journal of Fisheries and Aquatic Sciences 56, Nr. 7 (01.07.1999): 1298–306. http://dx.doi.org/10.1139/f99-074.
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We investigated habitat use of Atlantic salmon (Salmo salar) parr in experimental riverine enclosures made up of pool, riffle, and run habitats over a range of densities (0.1-1.25 fish·m-2) to test the implicit assumption in habitat modelling that habitat selection does not change with population density. Results indicated that habitat use changed with population density, with relatively more parr in pools and fewer in runs at higher population densities. Temperature influenced parr distribution, with relatively more parr in runs and fewer in riffles and pools at higher temperatures. Parr distribution was primarily affected by hydromorphological differences among pool, riffle, and run habitats. Effects of population density and temperature on use of pool, riffle, and run habitats were often as large as effects of hydromorphological differences among pool, riffle, and run habitats on fish distributions over the range of temperatures and densities observed. Results varied considerably, despite controlled experimental conditions. We concluded that habitat selection by juvenile Atlantic salmon parr may be density dependent and potentially quite variable.
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Paulus, David C. „HUMAN FACTORS LEARNING CURVE FOR THUMB-OPERATED TRIGGER RIFLE USING GYROSCOPIC FEEDBACK INSTRUMENTATION“. Biomedical Sciences Instrumentation 57, Nr. 2 (01.04.2021): 274–80. http://dx.doi.org/10.34107/yhpn9422.04274.
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Researchers interested in evaluating the biomechanics and human factors associated with using a new product recognize that skill development with the novel design is time-dependent. A learning curve is a plot that shows the time to complete a task using the product decreases as the number of training repetitions increases. A novel thumb-operated trigger system (Iron Horse, Blackwater Worldwide™) has been developed for the AR-15 style rifle with the intent to shorten the learning curve. The purpose of this research effort is to quantify the learning curve for the new device and to compare it to that of a standard mil-spec AR-15 trigger system. A previously-trained shooter dry-fire trained with both rifle systems for twenty consecutive days alternating lower receivers each day. The rifles were equipped with a gyroscopic instrument (Mantis X™) that tracked the movement of the firearm during the trigger pull process. The instrument has a timer to record the reaction time to an auditory signal for each shot, records the magnitude and direction of movement of the firearm, and calculates an accuracy score. There was not a significant difference (p>0.05) between the thumb operated and mil-spec triggers’ cycle times. However, the accuracy scores with the thumb operated trigger were significantly higher (p<0.05) than those with the mil-spec trigger.
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Jenzen-Jones, N. R. „Australia's Bullpup Rifles: A Developmental History of the F88 and EF88 Self-loading Rifles“. Armax: The Journal of Contemporary Arms VII, Nr. 2 (2021): 17–34. http://dx.doi.org/10.52357/armax75765.
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Following the experience of the Vietnam War, and in keeping with NATO military trends of the time, Australia began the search for a rifle chambered for a small- calibre, high-velocity cartridge in the 1980s. In 1988, Australia’s bicentenary year, the Austrian Steyr AUG was adopted as the F88 ‘Austeyr’. Manufactured domestically in Lithgow, New South Wales, the F88 went on receive a series of modifications under three distinct upgrade programmes, before being reconceived as the Enhanced F88 (EF88) from 2009 onwards. Now produced by Thales Australia, this latest iteration of the Austrian bullpup continues to serve the ADF around the world. In tracing the development history of what will soon be Australia’s longest-serving family of domestically produced rifles, the author outlines the challenges of maintaining a robust national manufacturing capability for small arms, and highlights solutions undertaken by Defence, industry, and other stakeholders.
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Subekti, Adaninggar Septi, und Aprilia Kristiana Tri Wahyuni. „Symbolism in Hemingway’s The Short Happy Life of Francis Macomber“. Journal of English Teaching, Applied Linguistics and Literatures (JETALL) 4, Nr. 2 (01.10.2021): 83. http://dx.doi.org/10.20527/jetall.v4i2.8755.
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This paper analysed Ernest Hemingway’s The Short Happy Life of Francis Macomber using New Criticism framework on symbolism. Comparisons of drinks, clothes, and colours paralleled the difference between Francis, a wealthy yet unconfident man, and Wilson, a man of masculinity. The next was the sitting positions of the characters in the car in which front seat symbolised authority and power whereas back seat inferiority and lack of confidence. Car symbolised protection, segregation, and power for Margot, whereas camp, and savannah foresaw Francis’ transformation from a wealthy person of comfort (camp) to a man of manly conviction signified with savannah offering wilderness. This transformation was also attributed to Francis’ overcoming obstacles symbolised with a lion and buffalos. Guns and rifles possessed by male characters indicated their dominance with Margot, the only female, practically left-out, except by the end of the story when she wielded a rifle shooting Francis dead.
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Kasahara, Tamao, und Alan R. Hill. „Effects of rifflestep restoration on hyporheic zone chemistry in N-rich lowland streams“. Canadian Journal of Fisheries and Aquatic Sciences 63, Nr. 1 (01.01.2006): 120–33. http://dx.doi.org/10.1139/f05-199.
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Stream restoration projects that aim to rehabilitate ecosystem health have not considered surfacesubsurface linkages, although stream water and groundwater interaction has an important role in sustaining stream ecosystem functions. The present study examined the effect of constructed riffles and a step on hyporheic exchange flow and chemistry in restored reaches of several N-rich agricultural and urban streams in southern Ontario. Hydrometric data collected from a network of piezometers and conservative tracer releases indicated that the constructed riffles and steps were effective in inducing hyporheic exchange. However, despite the use of cobbles and boulders in the riffle construction, high stream dissolved oxygen (DO) concentrations were depleted rapidly with depth into the hyporheic zones. Differences between observed and predicted nitrate concentrations based on conservative ion concentration patterns indicated that these hyporheic zones were also nitrate sinks. Zones of low hydraulic conductivity and the occurrence of interstitial fines in the restored cobble-boulder layers suggest that siltation and clogging of the streambed may reduce the downwelling of oxygen- and nitrate-rich stream water. Increases in streambed DO levels and enhancement of habitat for hyporheic fauna that result from rifflestep construction projects may only be temporary in streams that receive increased sediment and nutrient inputs from urban areas and croplands.
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Kriet, J. David, Robert B. Stanley und M. Sean Grady. „Self-inflicted submental and transoral gunshot wounds that produce nonfatal brain injuries: management and prognosis“. Journal of Neurosurgery 102, Nr. 6 (Juni 2005): 1029–32. http://dx.doi.org/10.3171/jns.2005.102.6.1029.
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Object. Penetrating brain injuries caused by self-inflicted gunshot wounds are very often fatal and survivors suffer serious disabilities. Recognition of a possibly more favorable prognosis for a specific type of injury, the submental or transoral handgun or low-energy rifle wound, prompted the authors to review their experience with patients who had attempted suicide in this manner. Methods. The records of 11 consecutive patients seen over a 10-year period (1992–2001) were retrospectively reviewed. Handguns were used by eight patients and .22 caliber rifles by the others. The patients presented with predominantly unilateral frontal brain injuries that required urgent attention. One elderly patient who had made an advance directive concerning care died. All other patients underwent craniotomy and repair of associated ophthalmological and maxillofacial injuries. Follow-up review ranged from 9 months to 3 years, during which time there were no repeated suicide attempts. All but one patient expressed satisfaction with their appearance and returned to a self-sufficient lifestyle. Conclusions. Self-inflicted submental and transoral handgun and low-energy rifle wounds may produce serious but survivable brain injuries if the path of the bullet is limited to the frontal area. Early aggressive management of brain, dural, and craniomaxillofacial injuries should return the patient to a highly functional neurological status and restore an acceptable outward appearance. Outcomes, therefore, appear to be much better for these patients than for most patients with a penetrating brain injury due to a self-inflicted gunshot wound.