"Rare" is a subjective term.
Yes, there were millions made during WWII (I've seen estimates of 6.5 million). The gun was designed by Winchester, but Winchester couldn't meet the military's demand, so their plans and specs were furnished to a diverse group of additional manufacturers.
The particular manufacturer and its condition are going to determine the value of your gun.
Up until a couple of years ago you could buy them inexpensively through the Civilian Marksmanship Program (CMP). CMP still has a few on auction every now and then, but those are the ones in very good condition -- probably not something to carry in the boat.
Reportedly South Korea has roughly 1 million M1 Garands and M1 Carbines that they want to sell back to the US. You can thank Obama for killing this deal.
I bought three from CMP (prior to the tragic boating accident). One (Inland) was for chooting -- the other two (one made by IBM, and one made by Standard Products) were for the great grandkids.
They make an awesome "truck gun" -- more maneuverable than an AK or AR --> ~~ 5.5 pounds and 36" long (but obviously less powerful).
The original .30 carbine ball ammo was specified to be 110 grain, FMJ, with a muzzle velocity of ~ 1900 ft/sec (resulting in muzzle energy of ~~ 900 ft. lbs. This gets it very similar to many .44 magnums loads fired from revolvers -- but the M1 Carbine holds a 20 round magazine.
Loaded with expanding ammo -- like the Cor Bon DPX load -- it's relatively potent (considering its size and lack of recoil). If the thugs ever start burning tires in the street, a la
Mogadishu, a .30 carbine with a small red dot sight (Aimpoint Micro T-1) would be good to have in a vehicle addition to a handgun.
I really regret that boating accident.
This post was edited on 11/23 at 6:55 pm