Report on the firing test to determine the limits of accuracy life of 4.7 A.A. gun T2

(Альтшулер В. Отчет о стрельбах по определению пределов точности орудия для 4.7" (119.38 mm) зенитной пушки T2).Report. Aberdeen Proving Ground, Maryland: Ballistic Research Laboratories. 1941. – 36 р.The effect of the firing on various elements of the complete round and gun are noted. During the life of the gun, the muzzle velocity decreases and the dispersion of muzzle velocity increases, affecting the probability of hitting. Assuming the rotating band continues to function, the accuracy life is estimated to be beyond 1400 rounds. It is thought that the rotating band of the projectile would be stripped before the predicted accuracy life would be reached and, therefore, that the stripping of the rotating band would determine the actual life of the gun.
Object of test. The object of the test is to get the effect of the firing on the functioning of the material and to predict at what point in the life of the gun it will be most advantageous to withdraw the gun from service.