USA609.6X2(BB-57 South Dakota&Atlas missile program)
USA609.6X2(BB-57 South Dakota&Atlas missile program)
One gun formerly used on USS South Dakota (BB-57) was converted to a 24" (60.96 cm) test gun by removing the liner, cutting the overall barrel length down to 492 inches (12.5 m) and then boring out the inside diameter to 24 inches (60.96 cm). The finished gun was part of the Atlas missile development program and was used to fire 5,000 lbs. (2,268 kg) projectiles at a muzzle velocity of 1,300 fps (396 mps) or 100 lbs. (45.4 kg) projectiles at a muzzle velocity of 3,600 fps (1,097 mps)
