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Prvi, Winchester, and S&B all make new production M2.

I've heard that any 150gr ammo should be fine.

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Ppu, and a couple other manufacturers make 150 gr 30.06 specifically for garands. It is marked as such on the box.

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Its crazy how the 30-06 has dried up all the sudden. I need 1k more rounds when it comes available...

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Can you spell H-A-N-D-L-O-A-D-I-N-G?

With all of the "It's in stock, it's not." over the last number of years I've been able to ignore all of it. While I got my components in 2006 in bulk so I can handload both 147grn 7.62x51 and 150grn M2 ball for 27¢ per rd, I also keep track from time to time about the current costs of the calibers (to compare to what I would have paid the last time) and just recently I calculated the cost of both calibers along with a number of others using April, 2018 prices.

The results I found for 1K rds (using 1K of 2,500ea purchase of 150grn bullets, 1K Win LR primers, 1K rds worth of a 8lb keg of Win748 powder, and the amortized cost of 5 reloadings of WCC brass I have[cost of the WCC ammo less the current component cost expended when I fired the first time]) was 42¢ per rd. As I've handloaded both calibers (and 14 others) for years and thousands of rds, the costs of the press, etc., have long ago been recaptured.

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Get the ported gas plug from Garand Gear and shoot any SAAMI-spec ammo in your gun.

Here's data to back that up. The M1 is stronger than most realize.

http://www.garandgear.com/m1-garand-ammunition

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I shot a whopping sixteen rounds of PPU 150gr soft points thru mine a couple days ago.  Used a ported gas plug, though.

Didn't seem to harm it any, but who knows.

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Actually that link shows that most commercial is safe with the standard USGI gas cylinder screw..no reason to waste money.

additionally the ported/vented/larger screws aren't CMP legal for the games matches etc.

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Its crazy how the 30-06 has dried up all the sudden. I need 1k more rounds when it comes available...

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There's plenty of 30/06 ammo at Walmart but unless it's labeled as Garand compatible then they don't.

Try to learn the reason why.

The Garand is designed around a specific pressure curve. Initial pressure at the breech is supposed to be at about 50,000-52,000 psi. That pressure is supposed to have dropped to 12,000-14,000 psi as the bullet passes the gas port in the barrel.

With powders much faster than IMR3031, pressure drops off too rapidly as the bullet travels down the barrel. At 50,000 psi breech pressure, gas port pressure will have dropped below 12,000 psi and operation will be erratic at best. Loading to get sufficient gas pressure for reliable operation will push breech pressures well over the 52,000 psi maximum.

With powders much slower than IMR4064, before breech pressures reach the minimum of 50,000 psi, port pressures will have gone well past the 14,000 psi maximum. This slams the op-rod back with excessive force. Eventually either the op-rod will become bent and out of spec. or repeatedly slamming the bolt into the back of the receiver will crack the heel of the receiver. Loading less powder to get the gas port pressure down below 14,000 psi will mean breech pressures well below the 50,000 psi minimum.

The use of bullets weighing more than 180 grains is also NOT recommended for the standard Garand.

Most reloading manuals are written for bolt action rifles and do not take gas operated semi-autos into account. The last couple of Hornady manuals have had excellent sections on loading for the M1 Garand rifle using only the powders with appropriate burning speeds. Another option is to replace the standard gas cylinder lock screw with an adjustable lock screw. These are made by Schuster and by McCann Industries and are sold by many retailers (Brownell’s, Midway, etc.). These allow the use of a wider range of powders, heavier bullets, and commercial ammo.

dukeofdata (CMP forum)