Hello, picked up an old Mossberg 42M off the EE awhile back. Nice rifle, only problem is that it has consistent failure to extract with spent .22LR cases. It ejects spent .22 short cases fine leading me to believe that the rifle was fed a steady diet of shorts that led to fouling over the years. I've stripped the rifle, cleaned everything and put hundreds of patches down the bore. Been over and over the breech with a copper tip cleaning rod. Still fails to extract all spent .22LR cases. You can feel it is the last 4mm of a long shell it has trouble with. A gunsmith I spoke with said you do not want to polish the breech because it could make things worse. Any ideas?
Help with fouling caused by firing .22 shorts?
- Thread starter fonestar
- Start date
Just an honest question: Are you sure that it is indeed chambered for 22LR?
If it is, you can do some more aggressive cleaning with something like foul-out, or scrubbing the chamber with bronze wool (wrap it around a worn-out cleaning brush and chuck it in a drill).
If it is, you can do some more aggressive cleaning with something like foul-out, or scrubbing the chamber with bronze wool (wrap it around a worn-out cleaning brush and chuck it in a drill).
delta1
CGN frequent flyer
The 42 should be chambered for the lr,l, and the short. I am thinking a lot of shorts were fired in this rifle since the primers are corrosive , I would think the chamber from where the short ends to the end of the chamber is pitted. The brass is expanding into this part of the chamber and sticking.
delta1
CGN frequent flyer
I do not think polishing it out is going to help much. Any removal in the chamber unless it is just something stuck on it will be making the chamber larger. Therefore making more room for the case to move into. I think you may have to stick with shorts or rebarrel. Other members more knowledgeable will be chiming in and perhaps a better solution.
Pretty common in a rifle that has been fed a steady diet of shorts. It's not fouled, the chamber just ahead of where the case mouth of a short would be is erroded and is ever so slightly larger, meaning your lr cases expand too much and the extractor is not strong enough to pull the over expanded case back through the chamber.
Rebarrel, sleeve or shoot shorts. Unless someone knows more than I do, which is always very possible.
Rebarrel, sleeve or shoot shorts. Unless someone knows more than I do, which is always very possible.
Been through all this recently with a 1934 Win 67. Don`t bother buying a pile of remedy items. I tried stuff for copper fouling, then I was sold stuff for lead fouling...I was sold Hoppes 9 and filled the barrel and left it for a week scrubbing a few times a day. I even tried the steel wool wrapped around the brush and chucked in a drill. Nothing worked or even made it any better at all.
The gun is not worth a liner or finding another barrel for. It will live the rest of its life eating shorts.
The gun is not worth a liner or finding another barrel for. It will live the rest of its life eating shorts.
Hmmm... not good to know I guess. I can feel it is just the first 3 - 4mm of the spent LR cartridge giving me trouble. I guess there is no harm in continuing to go at it hard with a bore brush and solvent. If it built up like that over the years it must be able to be worn down again too.
I think you're misunderstanding. It's not built up, it's pitted inwards ever so slightly. No amount of brushing will add material to the chamber.
delta1
CGN frequent flyer
He's right, it is either stick with shorts or rebarrel.
Before you do anything drastic, look at your spent brass! Chamber irregularities will show. If you can, do it with s, l, and lr. Also, give your chamber a good looking at. You may see your issue. Make sure all around your chamber looks happy too.
While you're at it, scrub your bolt, and be certain your extractors are looking good, and not hampered by crud.
While you're at it, scrub your bolt, and be certain your extractors are looking good, and not hampered by crud.
Okay, I see what you mean; the expansion is near the end of the cartridge. I have some JB bore cleaner that I will try and use along the entire length of the LR cartridge tonight (just a little at a time). If that doesn't work I will have the barrel sleeved. I don't have much use for a rifle that only fires shorts.
Interesting. I had never considered that sort of wear might be possible. Makes a lot of sense. Does it only happen with 22s that have seen LOTS of short through them? I really like being able to use short and LR in the same rifle.
I've never done it to a firearm so I won't speculate as to how many rounds it would take to happen. I've just seen it on a fair number of old .22s that saw heavy use back when shorts were far more popular than they are now.
