Mosin Extractor Leaving Marks on Brass?

M

Mosin-Marauder

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Mosin Bolt Issues

I was testing to see if some rounds would chamber in my Moline and I noticed the bolt was kinda hard to close on chambering the round. When I opened the bolt and ejected the round I see these little grooves on the head of the case that look like they were from the extractor. Is this normal? Here is a picture. Is this why the bolt is kinda hard to close? Now that I think about it, the bolt has been kinda hard to close non chambering since I got the rifle (as far as I can remember). Help would be appreciated.

 
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What little grooves?
I'm seeing nothing that leaps to the eye.

You'll likely get extractor marks to some degree on brass when cycled.

You never answered when I asked if you'd disassembled your bolt & made sure ALL cosmoline was removed.

Did you ever THOROUGHLY get the chamber & locking lug areas de-cosmoed?
Denis
 
I'm pretty sure all the Comso is not of the bolt. Not sure about the chamber. How would I get it out?

Also, the little grooves are 2 very minutes lines on the head that I couldn't get the camera to show.
 
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So, disassemble the bolt & clean it.
One potential cause of hard bolt operation.

The chamber's easy & most likely should have be de-cosmoed by now, but sometimes the locking lug recesses can still hold traces of grease & gunk that impede bolt closing.

Bent pipe cleaners soaked in solvent can get inside those areas (bend the cleaner in half, make a little 90-degree "hook" at the looped end & fish around inside behind the chamber).

Sometimes a solvent patch in a slotted-tip jag can be twirled around just inside that area with good results.

Might try an M16/AR15 chamber brush. The long "chamber" section of the brush obviously will be too small to do anything for the chamber, but the larger section at the rear may fit into the locking lug recess & loosen up old cosmo remaining.

Might try the Garand version, less commonly found today, but still available.

I'd avoid power tools like a drill to run a patch or brush.

And, if the grooves are too small for the camera to show, quit worrying about 'em. :)
Denis
 
all normal.. not to worry. except for stiffness... it might be junk. get a 45 caliber brass bruss and use it to scrub the chamber.
 
Perhaps it goes without saying, but I'm going to say it anyway. You should not chamber live rounds unless you're at the range or hunting or unless you have a setup that provides a safe backstop to contain an unintentional discharge.
 
Got some Q-tips and put some Hoppers on them and fished around in the locking lug recesses. For a few times it was easier to chamber, then it started to get hard to close again. I polished up on the rear of the bolt hand (where it contacts with the receiver) and it helped the smoothness a bit. Any more ideas?
 
Woild b putting the bolt in boiling hot soapy water and gently polishing them with a toothbrush or rag work? Then take some more q-tips to them?
 
Putting the DISASSEMBLED PIECES in boiling water & making sure they're clean & dry before lightly oiling & re-assembling should remove the bolt from the suspect list.

Just get any traces of cosmoline off.

You need to be careful about polishing, sometimes you can alter critical engagement surfaces & relationships and end up doing more harm than good.
Denis
 
Stiffness is likely cosmoline, but judging from the pics, the marking is normal. Even my Ruger M77 marks up the rims of my .270 win brass, if I cycle the same cases multiple times.
 
I don't see any extractor "marks"...

As everyone's told you, the bolt needs to be broken down and the components cleaned. Some boil, I use brake cleaner...

I don't know what kind of cleaning you did on the barreled action, but I would also suggest that to thoroughly clean the lug recesses (as well as the bore) that you remove it from the stock, and liberally spray inside the action-particularly the lug recesses- with the brake cleaner. It does a much more efficient job at removing cosmoline that powder solvent.

After cleaning, use a lightly oiled patch down the bore, and inside the action to prevent surface rust.

Working the camming surfaces of the bolt lightly with a dremel/Cratex wheel or fine grit paper to smooth them out helps- but the real test is whether there is a difference in resistance when chambering a round, vs. no round...

As Tahuna said it's very unlikely you have a real problem chambering factory ammo.
 
Tried to chamber the winchester ammo and the surplus ammo last night after I cleaned, dried, and lubed the bolt. Still some stiffness when closes the bolt on a round. When I do close the bolt on an empty chamber it is a lot easier. I'm kinda at a loss here, I could try to clean the recesses more, but I honestly don't think that would help as I've already got in there with q-tips and Hoppe's. Any other ideas?

What kind of brake cleaner do you recommend?
 
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Mo,
People give you suggestions & you ignore them.

A Q-tip won't get in the rear corners of the locking recesses completely.
You need something that's capable of cleaning at a 90-degree angle for best results & you simply can't get in there with a Q-tip.

You get impatient, want quick results NOW, and you don't want to take the time to do it right.

Scare up the AR15 chamber brush I mentioned, it has an enlarged 90-degree rear section specifically designed to deal with locking lug recesses.

Use the bent pipe cleaner mentioned, either with solvent or brake cleaner.

After which, use the patch in a slotted tip to remove the loosened cosmo & then oil up the locking lug recesses.

I'd keep the chamber dry, generally not a good idea to fire with it wet.
Absolutely NO grease in the chamber.

Not knowing how much resistance you're getting on closing the bolt with a round, hard to say how serious it is.
In my case, chambering has never been a problem on any of the Mosins I've had here; there have been a couple that required effort to open up AFTER firing.

In your case, I'm going to advise STRONGLY against letting a Dremel anywhere near your bolt.
If you remove too much material in the wrong places, you can adversely affect headspacing.
Denis
 
I'll pick up some pipe cleaners and let you know if it helps, don't have any at the moment, I'll also look for an AR-15 Chamber Brush. Sorry.

Is this it?
 
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In your case, I'm going to advise STRONGLY against letting a Dremel anywhere near your bolt.
If you remove too much material in the wrong places, you can adversely affect headspacing.
Click to expand...

You could grind away on the camming surfaces of the cocking piece and the bolt body to your heart's content with no effect on headspace. The only way to affect headspace is messing with the back side of the locking lugs on the bolthead. The bolthead "floats" just like a Savage and is independent of the rest of the bolt assembly.

There's not many things that can cause your symptoms. If, indeed, the bolt is harder to close when chambering a round, and it's NOT the bolt, or residue in the chamber or locking lug recesses, it has to be an issue with the chamber itself.

Try feeding empty brass.... this will rule out any issues with the timing of the extractor groove, boltface, etc. If the bolt closes without extra resistance on empty brass- that would only leave an issue with the leade/chamber IMO.
 
Did as you said and tried to chamber some spent casings. They had some difficulty feeding, the bolt would remove it from the magazine but about halfway to the chamber it would get caught or something. It would sometimes turn sideways. Same result chambering, the bolt would move up to the receiver and when I try to cam it it gets hard to close and the second stop before it closes it males this small *pop* before the bolt would chamber it (I heard these chambering live rounds aswell). Ejection was fine. I'll try the brake cleaner and pipe cleaners when I get some. That's about it. Also, here's a picture big the receiver if that's any help.
 
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Did I miss something here. If you were looking for extractor marks wouldn't you be looking at either the front of the rim or the side of it. Scratches on the head of the cartridge would come from the bolt face. Wouldn't it?

As far as cleaning with hot water, that is OK for removing the salts left by corrosive ammo. To get the carbon, copper , lead, grease and oils out you need good solvents. Some good flannel patches and a good cleaning rod. IMHO hoppes is the poorest choice of all. It isn't much better than shaving lotion I would suggest some Shooters Choice and a copper solvent some good stiff brushes and elbow grease. Q-tips are not sufficient to remove stubborn deposits. These things can all be bought at your LGS.
Never ever use sand paper on your bolt lugs ,just not a good idea. After you get it good and clean put a very small amount of good bolt grease on the cams and locking lugs. Good chance the bolt won't be stiff when you close it.
 
When chambering an empty casing, you need to "work it" over the feed lip of the magazine. It will likely hang up there, because there's no bullet to allow keep it in line, and allow it to slide up and into the chamber correctly. This doesn't apply in "reverse" (ejection), as you noted...

The suggestion wasn't to check feeding (which it won't do correctly), but rather to check whether closing the bolt was any different than you were getting with the loaded rounds.

Sounds like there may be an issue with the extractor- does it move freely?
When you disassembled the bolt, did you remove the extractor from the groove in the bolthead? I've seen them frozen in place with cosmoline trapped underneath them.
 
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