M1 Carbine Bolt Failure

[Devonai]

Saturday I was out firing my M1 Carbine. Ambient temperature was 10 F plus a bit of wind chill. After about thirty rounds I had a stoppage. I looked down and immediately noticed that the right bolt lug had sheared completely off.

The receiver was made in 1943, but I can't vouch for the age of the rest of the rifle. The bolt was the rounded-top type so it may have been a replacement.

After I get a new bolt, will it be necessary to check the headspace or will a function check be sufficient?

As for the bolt failure, any y'all encounter this before? I wonder if this is one of the infamous problems I heard about M1 Carbines during Korea. It would not surprise me at all to find out that it was the rapid heating and cooling of the bolt in that weather that caused the metal to fail.

 

[Ed]

There were 3 different types of bolts made for the carbine. 2 flat and one round. the first flat was changed to the second type of flat due to lugs failing, there was a cutaway portion that was filled in on the second type. The round was brought about to be able to handle the rapid fire of the M2. I think it was probably easier and cheaper to make also. Yes you should check the headspace when you instal another bolt.

 

[Sven]

What ammo were you shooting?

 

[Devonai]

I always use S&B, ever since I bought the carbine. I'd say I've put about 1000 rounds through it over the past few years.

There's some slight peening on the receiver near the raceway and locking area. That would seem to indicate that the entire action was under unusual stress at the time the bolt lug snapped. At this point I figure I'll send it to Fulton Armory for repairs (there's a six week backup at the local smith).