Tim the GI Carbine was made by a number of companies, IBM, Winchester Underwood, Inland. etc.
It shoots a 30 cal 110 grain full metal jacket bullet at about 2,000 feet per second. Roughly putting it in the power range of a hot 357 mag.
There is also soft point ammo available.
It's a fine small rifle. Many people say it's not powerful enough.
I've never heard of anyone that was shot in the chest with one say it isn't powerful enough.
A fairly good GI Carbine sells for about $600 plus.
There are some 1960's "civilian" Carbines, like the Universal selling in the $300 range.
The Carbine is about as simple as dirt. If you break or wear out a part, replace it and go back to shooting.
There are still a lot of GI parts around but the price is going up.
This is an M2 I dressed up a little.
The Carbine was my wife's favorite.
This is a M2 in 5.7 Johnson cal. (the 30 cal. necked down to 22 cal.)