M1 Carbines and checking headspace

[ABNAK]

So on a couple of gun boards, namely ones not really AR-centric, I've read recommendations to check headspace on Carbines if you have one. Obviously headspace is critical for just about any weapon, but for some reason I saw this warning repeated for M1 Carbines.

I recently bought an NRA "excellent" condition (and it indeed is) Postal Meter specimen. Haven't fired it yet. My buddy is a gunsmith and has a set of headspace gauges for the .30 Carbine round. I asked him to check the headspace and he kind of rolled his eyes thinking "Jeez, ABNAK is just being anal about stuff again". Well sure as hell it swallowed the No-Go gauge very easily. I didn't even worry about the Field Reject test. Fortunately my buddy has several Carbine bolts and he was able to swap them out until one dropped on the Go and did not drop on the No-Go. Problem solved.

I went over today to drink a brewski after work and he told me that my Carbine had gotten him to thinking about the one he owns. Instead of gauging first, he went outside and fired two rounds. No doubt he was thinking that mine was a fluke. Both the primers were flattened and backed out a bit. He was like "WTF?" Went inside and it swallowed the No-Go gauge. As luck would have it one of the remaining bolts he had gauged well and his is now GTG.

Bottom line with this long-winded post? I now whole-heartedly recommend checking headspace not only on Carbines you have that are recent acquisitions, but even ones you've had for awhile. Not sure why this seems to be more common with Carbines than, say, M1 Garands or M14 clones but it apparently is.

[mike_f]

My guess is:

1) Most M1 Carbines get shot a lot more than M1 Garands or M14 clones. Tons of low-recoil, cheap surplus ammo, and 30-rnd mags to feed it.

2) The world was awash in M1 Carbines & their parts for about 4 or 5 decades after WWII. Even carbines out of military service have been rebuilt/part-swapped (like to have all the same manufacturer, for instance) by people with a wide range of gunsmithing skills.

[notorious_ar15]

I've also personally seen a surplus M1 Garand fail a NO-GO gauge, then pass after installing a NOS surplus bolt.

[Bret]

I'm curious if M1 Carbine bolts were serialized to the rifle when they were manufactured (like an AK) or not (like an AR15).

[ABNAK]

I'm curious if M1 Carbine bolts were serialized to the rifle when they were manufactured (like an AK) or not (like an AR15).

Not that I'm aware of.

[Bret]

Interesting. Given that a bolt can make a significant difference in headspace with these rifles, it seems like they would be serialized.