The Garand does have some restrictions on ammo. One of the main ones is the use of a powder in the right burning range. A too slow burning powder (IMR-4350 H-4831 etc.) with a heavy bullet will cause high gas port pressures. These same high pressures can cause violent extraction, bending the operating rod, and other not so nice things. IMR-4895 is often called "the powder of the M1" with bullets in the 150 to 168 grain range and sensible charges of IMR-4895 (or H-4895) you should have no problems what so ever. A few other things to be watchful for if reloading for the Garand is to make sure the brass is sized properly and take care that primers are seated properly. Oversized brass will cause problems with chambering, and a raised primer may cause a slamfire. Take care to use a primer that is not too sensitive as this also can cause a slamfire. CCI primers are a good choice as they are not overly sensitive. CMP reccomends using either US Military M1 or M2 ball, M73 match, or any commercial ammo with bullets not exceeding 180 grains.
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Carlyle