Can we discuss the reliability of M-1 Carbines?????

[Patrick Chadwick]

The mag catch seats directly to the mag, but allows for a LOT of movement. And then there is some movement in the trigger group. Not nearly as much as what the mag catch allows though. Someone suggested a long time ago to me that this is all normal. Is it?

Not if my extensive sample of 1 (figures: one) carbine is a guide. No trigger group movement whatsoever. Catch snicks in quite snugly, without any slop. But a friend who is an experienced carbine shooter has marked his mags which appear to be a bit "touchy" and only uses a specific mag for competition. My present brute force solution is that I have acquired 12 mags, which I only load with 5 rounds each in order to avoid using a large range of compression on the magazine spring. I shall see in two weeks how it works out in competition.

Two separate competitions (25 and 50 meters) with 30 shots at each distance. 12 mags, each loaded with 5 rounds, which means I have 100% reserve for each competition session, so if a mag snags I shall simply drop it and insert in a fresh one. And, of course, I shall test cycle the lot at tomorrow's practice session. At least, that is my honest intention - laziness may creep in!

Whatever the reliability verdict, I find that my carbine is a delight to shoot, and makes a holiday from my shoulder-pounding big bangers.

[ChipS]

ABPOS:
IMHO, unless you are secretly the 'Man of Steel' (read Superman) you will have to put a carbine barrel in a vise to get any tight gas piston nut out. You just have to apply more torque on that skinny little barrel with that skinny little wrench than a man's hands can hold onto to resist. I put the flats along the rear barrel sides between two oak blocks in the vise with the barrel horizontal and the gas cylinder up. I lube the nut with penetrating oil well before I gently rock it lose with a little forward and reverse motion of the wrench to mash in the staking little by little and let the threads pass. I press the back side of the wrench head with my thumb hard against the nut to keep it from disengaging while I turn it. The wrench head tries to jump out of the nut recesses so I always mask the bottom flat of my barrel to prevent maring the finish if this happens. Also I make sure I am applying ROTATION ONLY to the nut and not applying any lateral force that might twist a swaged-on gas cylder on the barrel. I think this is best done by starting the wrench on the nut with the wrench handle in a horizontal position if possible. Most of the time you really don't have to exert too much force to get the nut moving. This operation is not hard and I believe it is pretty foolproof as long as you are carefull and use some common sense about how much force to apply to the wrench. If you are patient and just move it a little each way at a time the oil will get in and the nut will loosen up if it is not cross-threaded. It still may be a little stiff but once you flatten the staking and get a little oil in there it should come out of the cylinder with much less resistance. Others may have a better way of doing it but I have removed and replaced a lot of piston nuts this way and it has always worked well for me. The real danger is getting the nut back in without cross-threading it after you have cleaned the piston and cylinder - be very carefull, watch alignment very closely and do not try to muscle it back in with any more force than it took to run it out. Some recommend running a thread tap into the cylinder to clean up the staked threads but I have never found this to be necessary as long as I am very careful with my start-in alignment. I have not lost a patient yet. HTH

[DaveHH]

This eliminates the damage thread issue from the picture. And I would NEVER restake it.

A carbine that is not running well is usually in need of a new slide spring. It is remarkable how that one thing changes so many other little things that defy explanation. Cheap simple and usually works. The next issue is usually the mags. They are weak to begin with and the nubs that secure them wear easily. People tent to slam them in which accelerates the wear. Finally, I grease mine just like the big rifle, lots of grease as many parts are sliders.

I have a completely original 5.6 Winchester that has every part as issued including all the springs. It was used by me as a camping rifle for 30 years until I found out what it was. It functions flawlessly with GI or reloads. I believe this is because I take care of it, it is a low mile carbine and the chamber is clean and smooth.

Good fresh GI mags and slide spring and that thing will rock.

[ABPOS]

Thanks for the explanation on how to do it. Now to get enough courage to do it. Hmmmmmm......

What did you guys think about how much movement I'm having with an inserted mag? And where do you get "Good Fresh GI mags"?

[gunguy07]

Just a note on inherent reliability. In Germany during the 50's and 60's, we (rear echelon troops) were issued the carbine and were required to qualify once a year. My company had 250 men, each with their own carbine, firing around 500 rounds each during the week, including 300 yards slow fire. As "acting assistant armorer", I can assure you there were very few malfunctions, even at rapid fire. Also, there are no "good fresh GI mags". There are good GI mags and fresh mags, but the youngest of the GI mags is 50 years old or more.

[Patrick Chadwick]

This may be a beginner's question, but I still need to know the answer: should the tappet/gas piston be oiled or greased in any way? There must be a slight gas blowby through the piston assembly, as the piston/cylinder cannot have zero clearance. So does this lead to a "gas-cutting" effect over the years? And would/does greasing help, or is any grease merely blown out by the first few gas cycles?

[imarangemaster]

Do not oil the gas piston, at Least not heavily. It will carbonize and burn. I have soaked it with GI bore cleaner, though, and then blown it out with high pressure air.

[bonnie]

This has been an interesting read. I didn't see it covered in all the good comments but then I may have read over it.
Make sure the chamber is clean. Carbines never had a good chamber brush and this area gets neglected during cleaning. I use 9mm bore brushes and a short Chamber Maid rod, a flexible plastic coated steel cable, and clean from the receiver end.
You can also slide your cleaning rod in muzzle first then screw the brush in from receiver and pull it into the chamber to clean.

[ABPOS]

This has been an interesting read. I didn't see it covered in all the good comments but then I may have read over it.
Make sure the chamber is clean. Carbines never had a good chamber brush and this area gets neglected during cleaning. I use 9mm bore brushes and a short Chamber Maid rod, a flexible plastic coated steel cable, and clean from the receiver end.
You can also slide your cleaning rod in muzzle first then screw the brush in from receiver and pull it into the chamber to clean.

You know, after thinking about it and everything, this very thought came to me. I'm thinking it could be indicative of the kind of malfs I'm getting. Maybe the chamber needs a good working over. I don't think I've ever done it. I clean with a bore snake mostly. Although in the initial cleaning I think I used a traditional brush with hoppes down the bore. But I don't believe I ever worked on the chamber at all. Hmmmmm..............................

Thank you for the thoughts.

Let me ask this issue another way, you guys that have carbines that run, can you move your mags around a bit when they are seated?

[Patrick Chadwick]

you guys that have carbines that run, can you move your mags around a bit when they are seated?

This needs to be quantified. All mags must have some tolerance, so there will always be some movement. But how much is OK, and how much is excessive? If members could measure the fore-and-aft deflection of the mags that work, and those that don't, maybe we could establish a pragmatic statistical result on the lines of "up to ... they seem to work, above ... they are increasingly erratic".

And to start it off: here are two of mine:

Reliable mag....0.126" movement
Erratic mag.....0.106" movement

But there are other factors - in this case, the erratic mag has a much heavier spring. Because of these other factors, it will take quite a few measurements to reveal if there is any correlation between end play and reliability. I observe that the bottom of the mag is pushed forwards almost to the limit of the play when it is locked in, so end play may be largely irrelevant.

P.S: I shall now give the chamber a good clean!