37×145mmR

Ammunition was issued in the form of fixed rounds, consisting of: This shell used the M56 point detonating fuze.

The 0.16 lb (73 g) charge of M2 powder is a Hercules NG formula of single perforated grains with 0.03 in (0.76 mm) web and gives the projectile the prescribed muzzle velocity of 2,000 ft/s (610 m/s).

The tracer had a burning time of three seconds at the end of which it set off an igniting relay charge of 1.68 gr (0.109 g) of Grade A-5 Army Black Powder which ignited a relay pellet that detonated the charge, destroying the shell before ground impact.

The 0.16 lb (73 g) charge of M2 powder was Hercules NG formula of single perforated grains with a 0.03 in (0.76 mm) web and gave the prescribed muzzle velocity of 2,000 ft/s (610 m/s).

The propelling charge was 0.15 lb (68 g) of M2 powder of a Hercules NG formula with a single-perforated grain and 0.03 in (0.76 mm) web.