This manual is a guide for commanders and instructors in presenting instruction and training in the mechanical operation of the M1 rifle. It includes a detailed description of the rifle and its general characteristics; procedures for dis-assembly and assembly; methods of loading; an explanation of functioning; a discussion of stoppages and immediate action; a description of the ammunition; and instructions on the care and cleaning of both the weapon and ammunition. The material presented is applicable, without modification, to both nuclear and non-nuclear warfare.