This fixed round of ammunition is fired from the old model of German 5 cm short-barrel tank gun. The projectile has a plastic needlepoint ballistic cap, a mild steel projectile body, a tungsten carbide core, and a tracer. The cartridge case contains a propelling charge of diethylene glycol dinitrate tubular stick powder, and a charge of nitrocellulose granular igniter powder. An electric primer containing a quickmatch and black powder charge is also used.
The center of the projectile body is trimmed down, lightening the round and giving the ammunition an extremely high muzzle velocity. Armor-penetrating qualities are very good, but can be used only for short ranges due to the instability of the projectile in flight. On impact with armor plate, the plastic ballistic cap shatters and the tungsten carbide core is the only part that penetrates.
The projecile is unusual in that the forward bearing surface acts as the rotating band, and the rear bearing surface as the bourrelet. The rear bearing surface is in two parts, due to the crimping groove dividing it.
SPECIFICATIONS
| Weight of complete round | 5 lb., 3 oz. | |
| Weight of projectile as fired | 1 lb., 15.86 oz. | |
| Weight of tracer composition (kind not known) | 0.12 oz. | |
| Weight of primer composition (quickmatch and black powder) | 0.07 oz. | |
| Weight of igniting charge (nitrocellulose granular) | 0.45 oz. | |
| Weight of propellant | 1 lb., 2.69 oz. | |
| Length of complete round (overall) | 14.480 ins. | |
| Length of projectile w/tracer cup | 5.75 ins. | |
| Length of cartridge case | 11.342 ins. | |
| Diameter of bourrelet | 1.950 ins. | |
| Diameter of rotating band | 2.269 ins. | |
| Diameter of body midway of projectile | 1.258 ins. |
German: p. 307