压印在弹壳底部的数字,代表枪弹的制造工厂和制造年份。炮弹上的数字,依结构一般分为四个部分:引信上的数字,分别表示引信批次——制造年份——工厂代号;弹丸上的数字,一般依次表示适用火炮口径、炸药批次——制造年份——工厂代号; The number printed on the bottom of the cartridge indicates the manufacturing plant and year of manufacture of the cartridge. The numbers on the shells, according to the structure, are generally divided into four parts: the figures on the fuses respectively indicate the fuze batch - the year of manufacture - the factory code; the numbers on the projectile generally indicate the caliber of the artillery, the explosives batch - Year of manufacture - factory code;