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.458 SOCOM


The .458 SOCOM (11.63×40mm) is a moderately large round designed for a specialized upper receiver that can be mounted on any AR-15 pattern lower receiver. The 300-grain (19 g) round offers a supersonic muzzle velocity of 1,900 ft/s (580 m/s) and 2,405 ftlbf (3,261 J), similar to a light .45-70 but with a much smaller case. Prompted by the lack of power offered by the 5.56 NATO cartridge used in the M4 carbine and the M16 rifle, the .458 SOCOM came about from informal discussion of members of the special operations command, specifically Task Force Ranger's experience that multiple shots were required to incapacitate members of the opposing force in Mogadishu during Operation Gothic Serpent. Many Somalis would chew the drug Khat all day and the effects of the drug would both curb their appetite (in a country plagued by famine) and increase their pain tolerance.


Ammunition Type Damage Bullet Velocity (m/s) Barrier Penetration Armor Piercing
255gr Match 78 580 2.3 8
300gr Match 89 540 2.3 8
100gr CQB 68 914 1.75 7
500gr Subsonic 93.4 320 2.5 5
Lehigh CF 106.7 299 1.2 5
High Velocity SLAP 36 762 90 300
Incendiary Spotter 31 490 1.4 7
Note: Barrier penetration represents the rounds ability to go through walls and barriers. Armor piercing represents the rounds ability to penetrate body armor plates.