How to Identify an M1A
- 1). Evaluate the operational capabilities of the rifle. The M14 is a selective fire weapon and capable of semiautomatic or fully automatic fire. The M1A is semiautomatic only and cannot be converted to fully automatic.
- 2). Look for the selector switch and the distinctive cut-out notch in the stock. At the right rear of the receiver of every M14, a rectangular notch is cut out of the stock to accommodate the selective fire switch. The cut-out in the stock is always present on all M14s. No M1A has a selective fire switch, and no M1A manufactured after the late 1990s has a cut-out notch in the stock.
- 3). Compare the receivers. The receivers of both the M14 and M1A are made of 8620-grade steel. However, the fabrication process for each differs. M14s are drop-forged and milled while the M1A receivers are produced by a process called investment casting. So, the walls of the M1A receiver are slightly thinner than an M14. The different mechanical sound created by each receiver as it cycles rounds is reputed to be easily distinguishable by a shooter experienced with both weapons.
- 4). Determine if the rifle is bayonet-ready. M14s came from the factory with a lug beneath the muzzle for installation of a bayonet. Although very early productions of the M1A retained this feature, it was removed to comply with U.S. assault weapon laws. Today, no M1As have a bayonet lug.
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