There are thousands of articles and blogs on the subject of loading M2 ball ammo for the Garand. In most blogs I've read, someone asks for help with a recipe for standard G.I. M2 ball ammo which results in hundreds of responses about custom loads for competition, hunting, and plinking, but seldom results in a straightforward answer and usually leads to arguments about gas port pressures, do this, don't do that, etc.
I've been collecting WW1 and WW2 rifles for many years and enjoy the nostalgia of shooting the type of ammo that would have been available when the rifles were in service. Sure, I know how to custom load for them, to squeeze out every bit of accuracy, but what many shooters want is a standard G.I. ball load that will work in their Garand, as well as the 1903 Springfield, the 03A3, M1917 Enfield, etc.
When it comes to duplicating vintage ammo, I do months of research and when possible, I obtain some original rounds for testing, because these rifles are getting older every year and I don't want to destroy it by guessing.
Based on the WW2 Era M2 ball ammo I have fired, here is what I've been using to duplicate the rounds:
Remington brass, trimmed to 2.484”.
PRVI Partisan 150 gr. M2 bullets
46 gr. of IMR 4895
CCI #34 NATO style primer
Overall length is 3.330”.
Be sure to use a Lee Factory crimp die.
This load gives me the same recoil, the same point of impact and the same ejection pattern and the same velocity as WW2 Era M2 ammo.
You must remember that these rifles are well used and each barrel is worn according to the amount it was fired, which will result in velocity differences, so I will not quote the velocity from my rifles; just know that I was able to match the original ammunition exactly and can enjoy the experience of shooting these old rifles the way they were when they were in service.
If you use a different component than what I have listed, be sure to back off your powder charge by 2 grains and work up in small increments, to ensure the rounds are safe for your rifles. These loads are below maximum, but I have no idea of the condition of your rifles or loading equipment or how experienced you are in loading.
There are hundreds of other things I can say about loading for the Garand, but the intent of this was to provide a recipe that works, and I think you would be wise to research everything you can learn about loading for it. There are a lot of great books on the subject, and you should invest in them. Never guess what you think will work, because these old rifles are expensive, and your eyes and fingers can't be replaced. Happy shooting!!