: Look for "MODEL OF 1911 U.S. ARMY" (or Navy/USMC) on the right side for early models. Later M1911A1 models may have manufacturer-specific stamps like Ithaca or Remington Rand, though Colt was the primary producer.
While most parts are interchangeable between the M1911 and M1911A1, specific external features differentiate the two military eras: colt-1911-military-parts
: Frames often bear the initials of military inspectors (e.g., "G.H.D." for Guy H. Drewry) near the magazine release or trigger guard. 2. Physical Differences: M1911 vs. M1911A1 : Look for "MODEL OF 1911 U