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Ammunition Design Practice
Published in Donald E. Carlucci, Sidney S. Jacobson, Ballistics, 2018
Donald E. Carlucci, Sidney S. Jacobson
To the rear of the long cylindrical portion of the gun (the bore) is the chamber, shown in Figure 4.7. The tapers shown facilitate the removal rearward of the spent cartridge case that hugs the chamber wall. During the firing cycle, the case swells because of the internal pressure and firmly contacts the chamber wall sealing the gases from exiting rearward. When the pressure decays, a properly designed case comes away from the wall and the tapers ensure that it does not stick in the chamber. When a fixed round of ammunition is loaded into the chamber, the rear face of the tube provides the stop and seat for the rim of the case. During the expansion of the pressurized case, the forcing cone of the chamber forms the seal for the hot gases by the extrusion and engraving of the rotating band in a rifled bore or the extrusion of the obturating band in a smooth bore. The ratio Dc/D is known as the chambrage, an important characteristic of the design. Large values of the chambrage tend to cause turbulent flow of the gases as they enter the bore. Such turbulence contributes to the erosion of the bore surfaces.
Classification, Comparison, and Correlation
Published in F. Brent Neal, John C. Russ, Measuring Shape, 2017
“Form follows function” applies to manufactured items as well as natural ones. Handguns are a useful example. There are three different modern types: automatic, revolver, and derringer, plus a wide range of antiques. Derringers have a separate barrel for each cartridge (sometimes two, four, or even more) and are among the smallest in size. Revolvers have a separate chamber for each cartridge but share a single barrel. Automatics load cartridges from a clip, usually in the grip, into a single chamber. Antique handguns include flintlocks and percussion designs and are muzzle loaded. The different design approaches dictate to some extent the physical form of the weapon, but within each class there are major differences because of individual designer’s decisions and the somewhat different uses for which each design may be intended. Figure 6.67 illustrates a few of the wide range of shapes that result.
Safe Handling of APIs and Drugs
Published in Sam A. Hout, Manufacturing of Quality Oral Drug Products, 2022
All BSC must go through a thorough cleaning at least annually or if a large spill occurs which contaminates more than 50% of the BSC’s working surface. For most purposes, cleaning can consist of using a surfactant (detergent) to clean the inside of the chamber, followed by a water rinse.
Movement of amphibious rifles fixed on the mount when shooting and operating underwater
Published in Waves in Random and Complex Media, 2022
Hung Nguyen Van, Doan Dao Van, A. M. Zenkour, Phung Van Minh, Do Van Thom
The position of the amphibious rifle mount in the water tank establishes the amphibious rifle's movement model while firing underwater, as seen in Figure 3. The amphibious rifle's motion is determined by the following equation [13]: where is the total mass of the amphibious rifle and the upper mount, is the acceleration of the amphibious rifle and the upper mount, is the force of shot depending on the barrel gas pressure, is the force on the gas chamber, is the return spring force of amphibious rifle, is the collision force between the bolt carrier and the receiver, is the water-resistance force, and are the friction forces on the sliding rail, is the force of spring on the mount.
Internal reinforcement mechanisms for gelatin bird projectiles for artificial bird impact tests
Published in Mechanics of Advanced Materials and Structures, 2023
Gang Luo, Fengqi Zhang, Ziming Xu, Haiyang Zhang, Lulu Liu, Wei Chen
In a bird-impact test using a GBP launched by an air gun, the GBP is generally placed in a sabot. When the compressed air in the air chamber of the air gun is released, the sabot is pushed to accelerate in the gun barrel and then separates at the separator, whereupon the GBP continues under its own inertia and flies out to impact the target. When designing and developing test equipment and parameters, the interior ballistic motion state of projectile must be considered. According to reference [39], a simplified schematic of the primary air gun is shown in Figure 1.
Instability Mechanism and Engineering Cases of the Surrounding Rock in Deep High Stress, Weak Strata Chambers
Published in Energy Sources, Part A: Recovery, Utilization, and Environmental Effects, 2020
Sijiang Wei, Peicheng Gao, Chongyang Wang, Sheng Zhang, Meng Wang
From January 2007, according to the deformation and failure of the chamber, the section was enlarged compared to the original support, and the high-strength bolt and anchor cable were used for combined support. The roof and walls of the chamber were strengthened by bolt-cable coordination. The floor failure zone was excavated. Then, concrete was used to strengthen the floor.