Shooting commercial?

[AKA Hugh Uno]

There is some new-manufacture Garand-specific ammo. It will be marked as Garand ammo, ie "30-06 Garand"

The issue is burn timing. Modern powders burn quicker than the spec for a Garand and the faster burn rate can throw off the timing of the Garand's semi-auto mechanism.

Bob

You have this backward. The issue is PORT PRESSURE and faster powders would result is LOWER gas port pressures. SOME of the "ULTRA" magnum "Super Performance" type stuff uses SLOWER powders which MIGHT increase port pressure.

If you simply follow the link supplied by emmagee1917 (below/above) and HERE: Shooting Commercial Ammunition in your M1 Garand which details Eric-C's extensive pressure testing at the GAS PORT, you will quickly discover that it is difficult to FIND much commercial that ISN'T Garand safe. In other words, the advice about 150 grain commercial was pretty good.