One was probably responsible for more enemy KIA than any other semi automatic rifle in history, given over 6 million were issued during WWII and were a mainstay of our men in Korea, and the early part of Nam. Millions the went to allies-Korea got tons, and Columbian Military Police we met at checkpoints on the Pan-American highway, were armed with what were once US military MI Carbines. a long deceased CSM I used to know-served in the Pacific in WWII (Rangers), Korea (Rangers) and Nam (Special Forces) was cleaning an MI carbine at the range where I was a staff professional shooter and he was the range master./ Some gunshop commando said "those MIs weren't any good" and the CSM said, in a quiet voice-"well son, about 27 or so Chinamen might disagree with you if they were around to talk". In Korea, he was commanding three machine gun positions when Chinese "Volunteers" tried to come around through a pass to flank the machine gunners and the CSM took a position guarding the pass, with two MI Carbines and a satchel full of 15 round magazines He noted after he shot about 27 of them, they figured out that they weren't getting through the pass-and at that time, the bad weather lifted and the Sabres came in and strafed and napalmed the field where the Chinese were assembled and trying to attack the machine guns. The CSM earned a silver star (one of two, IIRC) for that.
Anyway, he used his two MI carbines to kill more enemies of the USA than AR 15s have been used by our military