This is a hotly debated topic about whether or not you can use regular 30-06 factory loads.
Most of them are running at near full SAAMI pressure and obviously designed for bolt guns.
Garands are strong suckers but the old ball ammo they were designed around is not running at the same pressure as full house 30-06 loads. When you start to run heavier bullets, it's even more magnified.
There are people online who swear up and down that full house ammo won't hurt the gun.
ME, I shoot 150 gr. FMJs over 48 gr. of IMR 4064, or 168 gr. HPBTs over 46 gr. of 4064.
Period, end of story. I do not feed it anything other than that. I'm sure it can take more, but the op-rod is expensive and I don't see a reason to stress it at all.
That 150gr. load very closely approximates M2 ball, which is what I'd recommend getting ahold of if you are not a handloader.
Correct. It’s not a flat “modern loads pressure” it’s the pressure at the gas port. The Garand was designed around the powder and ammo of the period which was in the IMR 3031 to IMR 4064 burn rate. Slower powders will be at a higher pressure further down the barrel and therefore too high at the gas port, which is near the muzzle in a Garand.
To put it another way, Garand loads should be worked up taking chamber pressure into account just like every other rifle… while also taking port pressure into account. You have to watch pressure at both ends of the barrel.
People take that information and say that since heavier bullet loads “must” be loaded with slower powder, then they aren’t safe to use. Well maybe they are loaded with slower powder and maybe they aren’t, but it’s probably not worth the risk with plenty of known safe ammo out there.
It’s possibly- possibly- just as likely a random 150 grain bullet load is loaded with a powder out of safe burn rate range. If you don’t know what it was loaded with, you don’t know.
The best article on this was published in the American Rifleman in the 80s and written by John R, Clarke:
Reloading For The M1 Rifle - J. Clarke | PDF
It has loads for bullets up to 190 grains, but using nothing slower than IMR4064. The velocities with the heavier bullets won’t be the highest because of that, but the port pressure will be safe.
I’ll wholeheartedly back up the suggestion for Scott Duff’s books, particularly his “Garand of WWII” for yours.
“The Complete M1 Garand; A Guide For the Shooter” by Jim Thompson is also good, with some loading data. It’s like it says; for the shooter and not the collector.
My favorite Garand book is “Hatcher’s Book of the Garand” by Gen Julian Hatcher. The match prep info is long-outdated, but it has history, development, battle use, match use, and care by someone who was there for all of it.
Perhaps most important of all, the book begins by giving the correct pronunciation of “Garand” (rhymes with “errand”). He knew the man; I think he’d know.
