A couple of months ago, my wife and I borrowed my father's M1 Carbine to shoot in the Monumental RPC match. After a couple of sighters, she started shooting for score and began having jams like this:
I wish I had taken the time to get a better picture...but...oh well At least it's something...
We were using cheap imported mags that were known to be finicky. Since we wanted to both shoot for score before the next cease fire, we just soldiered through. I'd say out of 60rnds total between us, we probably had 7ish jams. At first, she was kicking the jammed round out and rechambering. I found I could just pull the bolt back a little and let it drive the offending round in.
After the match, I tried a known to be reliable mag, to ease my mind...and it did the same thing. Uh-oh! I had Dad's whole box of M1 stuff, so I tried several combinations of three "good" mags and three types of ammo (one being the milsurp ammo that this carbine has been fed for my entire life, new PPU and new Rem). Every combination would jam at some point...not every round, and not always at the beginning or end of the magazine, but always in the same fashion.
The rifle was (or started out) clean and well lubricated. Nothing has been done to it recently (heck, it's just been resting since the Carbine match the year before, when it worked fine).
The gas piston has not been staked in. When I took it apart to clean it, the nut was loose, but only by about 1/8 turn from being finger tight (last year, I'm sure I tightened it with the appropriate wrench before it went into hibernation). In the past, I'm pretty sure it has been looser and still worked. Neither the piston nor the nut appeared damaged, worn, or excessively dirty. I don't think this is the problem. At some point, I do want to stake it. I believe this is done with a brass rod "beaten" into the hole of the gas chamber?
So what says the braintrust? Stake the piston? (yeah...yeah...it's been waiting 40+ years for that, but we'll get to it eventually). Springs?
I wish I had taken the time to get a better picture...but...oh well At least it's something...
We were using cheap imported mags that were known to be finicky. Since we wanted to both shoot for score before the next cease fire, we just soldiered through. I'd say out of 60rnds total between us, we probably had 7ish jams. At first, she was kicking the jammed round out and rechambering. I found I could just pull the bolt back a little and let it drive the offending round in.
After the match, I tried a known to be reliable mag, to ease my mind...and it did the same thing. Uh-oh! I had Dad's whole box of M1 stuff, so I tried several combinations of three "good" mags and three types of ammo (one being the milsurp ammo that this carbine has been fed for my entire life, new PPU and new Rem). Every combination would jam at some point...not every round, and not always at the beginning or end of the magazine, but always in the same fashion.
The rifle was (or started out) clean and well lubricated. Nothing has been done to it recently (heck, it's just been resting since the Carbine match the year before, when it worked fine).
The gas piston has not been staked in. When I took it apart to clean it, the nut was loose, but only by about 1/8 turn from being finger tight (last year, I'm sure I tightened it with the appropriate wrench before it went into hibernation). In the past, I'm pretty sure it has been looser and still worked. Neither the piston nor the nut appeared damaged, worn, or excessively dirty. I don't think this is the problem. At some point, I do want to stake it. I believe this is done with a brass rod "beaten" into the hole of the gas chamber?
So what says the braintrust? Stake the piston? (yeah...yeah...it's been waiting 40+ years for that, but we'll get to it eventually). Springs?