Q: I recently purchased an M1 carbine manufactured by Quality Hardware that has a bayonet lug. Is this part original to the gun or was it added later?
A: It was added later. More than 6 million M1 carbines were made over the course of the war, with production starting in mid-1942. The so-called “Type 3” (T4) barrel band with the integral bayonet lug was standardized in late 1944. By this time, the only carbine prime contractors still in production were Winchester Repeating Arms and the Inland Mfg. Division of General Motors.
The barrel bands with bayonet lugs were used in the last few months of production on M1 and M2 carbines manufactured by the two companies, and none of the carbines made by the other prime contractors left the factory with bayonet lugs.
Most of the carbines seen today, however, were subjected to the extensive post-war arsenal overhauls. That resulted in many of the original factory parts—especially barrel bands and rear sights—being replaced by later-pattern parts.
By the time production ceased in August 1945, Inland Mfg. Division of General Motors had produced 2,362,097 M1 carbines. Winchester made 828,059, followed by Underwood Elliott-Fisher at 545,616, Saginaw Steering Gear 517,212, IBM at 346,500, Standard Products at 247,000, Rock-Ola (yes, the juke box maker), with 228,500, Quality Hardware at 359,666, National Postal Meter at 413,017 and Irwin-Pedersen made a few thousand.