Yamaha K-31 Technical data Download

68, 69
Part 2
47 Ammunition for long rifle, musketoon (short rifle), Automatic rifle, and machine gun are
delivered to troops ready to fire. They are all the same.
The cartridge is composed of the bullet (projectile), the propulsive charge, and the case.
The bullet is inserted into the neck of the case. In order to hold the bullet tightly and seal the
interior of the case, the case neck is crimped into a circular groove near the base of the bullet. In
addition, a grease ring at the neck crimping seals the cartridge.
The propulsive charge placed inside the case, is composed of stick powder, which produces very
little smoke upon discharge (nitrocellulose).
The case is composed of brass. The sides of the case gradually thicken near the base. The primer
is placed in a special pocket located in the base of the cartridge. When a shot is fired, the point of
the firing pin strikes the center of the primer where the percussion material is placed. The
percussion material then creates a spark that ignites the propulsive charge.
The manufacturing data for the cartridge is stamped onto the base of the cartridge around the
primer. The letters and numbers indicate the following information:
Left Letter: Source of the case material
Right Letter: The initial of the munitions factory
Upper Number: Month of manufacture
Lower Number: Year of Manufacture
Common Rifle Cartridge 11
Armor Piercing Cartridge
Fig. 29 Ball Cartridges
Tracer Cartridge