TM 43-0001-27, Army Ammunition Data Sheets - Small Caliber Ammunition, FSC 1305(PDF). Washington, D.C.: Dept. of the Army. 29 April 1994. : The standard .38 ball M41 cartridge first issued in 1956 had a pressure limit of only 13,000 CUP for a bullet velocity of 725 ft/s (221 m/s). After the M13 was withdrawn from service, a higher-pressure cartridge, the Caliber .38 Ball, Special, M41 was introduced. The M41 Special cartridge had a revised pressure rating of 16,000 CUP, giving a velocity of 950 ft/s (290 m/s).
