When I referenced M1, I meant the Garand. I use .30-06 for deer. I knew they used the M1 carbine in WW2, but thought this was straight up .30 cal too...like the M2.
It’s very hard to beat a “Garand” !
The M1 Rifle is known as the Garand. Uses the high-powered bottle-necked .30-06 cartridge.
M1 Carbine and M2 Carbine use the .30 Carbine tapered cartridge, with about 1/3 the energy of the .30-06.
I’m not sure what you mean by “straight up .30 cal”. They are both .30 cal, nominally .30 inches in diameter (actually .308). But use different bullet weights, and very different cases.
They are two of a plethora of .30 caliber rifle rounds, including the .30-30 and .308, that are not interchangeable.