Basically the M14
From Wiki...
Springfield Armory, Inc. of Geneseo, IL, produces a semi-automatic-only version of the M14 rifle. The standard rifle is known as the M1A. The company produces several variations of the basic rifle with different stocks, barrel weights, barrel lengths, and other optional features. The Springfield M1A and its model variants have been widely distributed in the U.S. civilian market and have seen use by various law enforcement agencies in the U.S. Springfield Armory, Inc. also produce the SOCOM series and the Scout Squad Rifle, based on the short-barreled version of the M14. The SOCOM 16 comes with provisions to mount a red dot sight and the SOCOM II adds railed handguards to the package. Springfield Armory's M21 tactical is a civilian version of the M21 Sniper Weapon System currently in use by the U.S. military.
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