Accession Number : AD0009075
Title : SEVEN SHOT 30MM BALLISTICS GUN
Descriptive Note : Final rept.
Corporate Author : NAVAL PROVING GROUND DAHLGREN VA
Personal Author(s) : Rucker, L D
Report Date : Apr 1953
Pagination or Media Count : 36
Abstract : An investigation was made of the interior and exterior ballistics of British 30-mm Aden projectiles and a 7-bore single-barrel weapon. The cartridge consisted of a modified 3-in./50-cal case fitted with a 0.5-in.-thick brass plate and 7 projectiles. The grooves of adjacent bores in the barrel were separated by 15/64 in. Recoil and counterrecoil were accomplished with four 40- mm hydraulic buffers and a 3-in./50-cal barrel spring, respectively. The gun was 59.5 in. long and weighed 827 lb. An 0.85-lb charge of IMR-4903 powder gave a 2150-fps muzzle velocity. The test data indicated that: (1) the velocities of the leading and trailing projectiles varied by 4.5%; (2) the center projectile emerged first and had the highest velocity and the least yaw; (3) up to 31 deg of yaw occurred at 150 ft; (4) weighting the central projectile to 0.73 lb did not decrease yaw; and (5) the average maximum dispersion was 28.6 mils at 2000 in.
Descriptors : *EXTERIOR BALLISTICS , *NAVAL GUNS , DISPERSING , INTERIOR BALLISTICS , HIGH VELOCITY , YAW , EXPERIMENTAL DATA , PROJECTILES
Subject Categories : Guns
Distribution Statement : APPROVED FOR PUBLIC RELEASE