This should be a known to everyone who owns or shoots vintage US Military Rifles. Commercial .30/06 is NOT the same as Ball M2, the ammunition the M1 Garand was designed for. Ball M2 is also good for the high number Springfield 03 and the 03/A3. (High number Springfield has a serial number above 800,000, Rock Island 03 above 285,507)
Lots of new shooters. And with ammo in short supply some may think all .30/06 is the same. I still see low number Springfield brought into my shop, and their owners don't know there was a change in heat treat making for high serial number an low serial number rifles. In the low number the carbon may have been 'burned' out of the steel during heat treat, making for a brittle action. Too powerful of loads or too heavy a bullet in the Garand might bend the operating rod. Not a cheep (low cost) part to replace. There is modern ammo produced for these rifles by Federal and Hornady, and maybe Sellior & Belloit loaded for the M1 Rifle. (hard to find, like all ammo right now!)I read the CMP post and thought, "Isn't this pretty well known?" Then I thought with all the 'new' gun owners from the past year, maybe it was a worthwhile reminder. I like your follow up post @shortgrass - good to help people differentiate what is okay and what is not in these mil surp guns.