.22 Eargesplitten Loudenboomer

.22 Eargesplitten Loudenboomer
Type	Rifle cartridge
Place of origin	United States
Production history
Designer	P.O. Ackley
Designed	1960s
Specifications
Parent case	.378 Weatherby Magnum
Case type	Flask barrel
Bullet diameter	.224" - 5.56mm
Rim diameter	Magnum .537"
Ballistic performance
Bullet mass/type Velocity Energy 50 gr (3 g) Machine gunpowder 106gr. 4,160 ft/s (1,270 m/s) 1,921 ft·lbf (2,605 J) 50 gr (3 g) H570 100gr. 4,170 ft/s (1,270 m/s) 1,930 ft·lbf (2,620 J) 50 gr (3 g) H570 102gr. 4,390 ft/s (1,340 m/s) 2,139 ft·lbf (2,900 J) 50 gr (3 g) H570 105gr. 4,600 ft/s (1,400 m/s) 2,349 ft·lbf (3,185 J)
Source(s): quoted "Guns and Ammo Magazine", B. Hutton

.22 Eargesplitten Loudenboomer is a cartridge for a rifle.

It was invented in the 1960s by P.O. Ackley to set a world record for firing bullets at over 5000 fps (1524 m/s). The round failed to reach the desired velocity, but reached 4600 fps with a 50 grain bullet and 105 grains of H570 powder. It is based on the .378 Weatherby Magnum cartridge case, necked down to .224 calibre.

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