HE cartridge M48 is used primarily for fragmentation, blast and mining.
This cartridge consists of a relatively thin-walled forged steel projectile filled with a 1.49 pound bursting charge of TNT. The projectile is stab crimped to either the M18 or M18B1 cartridge case. The propelling charge consists of 1.15 pounds of M1 propellant assembled loose in the cartridge case. The M22A3 primer is press-fitted in the base of the cartridge case.
The projectile is olive drab with yellow markings.
When the percussion primer is struck by the firing pin of the weapon, a small amount of black powder in the primer tube is ignited. Sparks and flame from the black powder ignite the propelling charge. Gases from the burning propelling charge drive the projectile through the bore of the weapon. Spin is imparted to the projectile by the engagement of the rotating band with the rifling in the bore. This spin stabilizes the projectile in flight. When the fuze functions, either over or on the target, the bursting charge detonates with both blast and fragmentation effect.
Filler - TNT or 50/50 Amatol (1.49 lb, 0.67 kg)
Primer - M1, M1A1, M1A2, M1B1A2, M64
Propelling charge - M1
Supplementary charge
Length, overall - 23.5 in, 596.9 mm
Iraq Ordnance Identification Guide (2004)
TM 9-1300-203, Artillery Ammunition (1967) (and here) (and here)
TM 9-1300-203, Ammunition for Antiaircraft, Tank, Antitank and Field Artillery Weapons(1960)
TM 9-1904, Ammunition Inspection Guide (1944)
US Navy Bomb Disposal School, US Army Projectiles (1943)