Wireman
Member
I have been wrestling with an intermittent M1 Carbine problem. This is a mixmaster commercial Universal drilled on left side for a scope. Problem: cartridges will feed, fire and eject normally when the bolt is operated by hand. After 2 or 3 rounds (various magazine types) the bolt stops 1/8" short of battery. Pushing the bolt forward by hand chambers the round, which then fires normally. Reason: the extractor does not snap over the rim.
Original obvious problem: Gas piston and gas piston nut were missing. Owner does not know the history of the rifle. It now has a new piston and lock nut, although I can't determine the style or if it can be used in this particular rifle. Gas port is clean, piston chamber clean. New action spring. Cleaned out the bolt, ejector and extractor. The only suspicious thing is the power of that extractor spring. I know next to nothing about M1 carbines, but that extractor spring seems very stiff to me - the bolt is clean and lubed and (as above) will always chamber a round if the bolt is pulled back and released manually.
Is this a type of short stroke problem? If the bolt is not thrown all the way back, the action spring won't have enough power to chamber the next round. Incorrect piston, weak ammo? Should I open up the gas port a little?
None of the M1 carbine ammo I have seen has the velocity listed on the box. Is that typical?
Thanks!
Wireman
Original obvious problem: Gas piston and gas piston nut were missing. Owner does not know the history of the rifle. It now has a new piston and lock nut, although I can't determine the style or if it can be used in this particular rifle. Gas port is clean, piston chamber clean. New action spring. Cleaned out the bolt, ejector and extractor. The only suspicious thing is the power of that extractor spring. I know next to nothing about M1 carbines, but that extractor spring seems very stiff to me - the bolt is clean and lubed and (as above) will always chamber a round if the bolt is pulled back and released manually.
Is this a type of short stroke problem? If the bolt is not thrown all the way back, the action spring won't have enough power to chamber the next round. Incorrect piston, weak ammo? Should I open up the gas port a little?
None of the M1 carbine ammo I have seen has the velocity listed on the box. Is that typical?
Thanks!
Wireman