Problem with KAR 98k

[CCubed]

I hate reposting stuff, but I wasn't getting many hits in the "technical advice" (or whatever it is) forum section. Anyway, here's the deal.

I took my 98k out the other day, after cleaning it. I got most if not all the cosmoline out of it, and did a good job cleaning the barrel. It looked fine. I took it out and put some lightly corrosive, FN 8mm rounds through it. From the get-go, I knew I had a problem.

I had the hardest time lifting the bolt handle up, to recock the hammer and open the bolt. Some thing's wrong. The weapon cycles these rounds fine; I can't find anything wrong with the bolt. The barrel and the chamber seem fine - no serious or deep pitting, or anything like that. These rounds fired fine through my M48 Mauser.

Now, this particular bolt doesn't have quite the "snap" which my M48 bolt does. When I have the safety completely off and I open my M48 bolt, it snaps back a bit. The bolt on the 98k doesn't do that, at least not as well. It does seem worn.

My concern is that the one and only person who responded to my post in the technical forum said that he thought it could be due to problems with the chamber, etc. Honestly, I'd rather have problems with the bolt; they're easier to fix. If, however, I'm having, let's say, headspace problems, can it be fixed and if so how? (I know that a gunsmith would have to do it.)

[Popgunner]

I had the same problem with one of my M-48's-hard bolt lift & also the bolt was stiff to close when loading a cartridge. My problem ended up being a couple of little smeared chunks of brass hiding in the bore where the bolt lugs ride. I used a 20 ga brass brush & got them out. The gun now shoots great

[CCubed]

Popgunner,

did you see the brass come out while cleaning? After this whole escapade, I took the gun back & cleaned it & I used a 20 gauge brush on the bore, just like you did. I can't remember noticing anything coming out, but I wasn't really paying close attention. So, my question is, If that was my problem, would it be, like, blatantly obvious when the brass comes out, or is it something which, if I'm not looking for I could have easily missed?

I'm just wondering 'cause I hope this is the answer. :-)

[JLA]

you could have a number of problems... some of the earlier mausers had a .318 dia. called the js bore. most commonly found on the early ww1 era rifles. most commercially loaded ammo is set at a SAMMI max of 35000 CUP in light of the more common .323 dia. bullets being shot down the bore... also, some of the mausers i have worked on in the past few years have been so worn that the bolt had an inch of movement in all directions when open, causing headspace problems... most are relatively safe to shoot as long as you stick with the SAMMI max listed above... look for the primers being slightly extruded from the rear of the shellcasing after firing, this is a clear indicator that the rifle has a headspacing problem. also, most of the surplus mausers you are gonna find are mix and match, which usually doesnt cause a problem, but, for instance, lets say they take a mauser that got issued at the beginning of the war, and was passed from soldier to soldier and saw 20,000 rounds of use before the barrel was ran over by a half-track and bent. they then take that bolt and reciever and throw them into a big ol' box of "spare parts" in a warehouse for 40 years, and then get paired back up with an unissued barrel and stock that sat in a factory somewhere for that same 40 years... point is, it happens, your best bet is probably to have a competent gunsmith look at it to determine the problem...

[CCubed]

Check this out:

http://www.rifleshootermag.com/gunsm...eadspace_0612/

If your chamber is below minimum, and thus too small, you can have problems with bolt function. The cartridge, being crammed into the short chamber, prestresses the locking lugs of the bolt. Once fired, the bolt handle may be hard to lift.

Sounds like a possibility. The thing which was most mystifying, to me, was that the rifle wasn't having problems cycling the rounds. The weapon HAD to be fired in order for me to have difficulty unloading each round.

I'm definitely going to have my gunsmith look at it, but I'm not crazy about the idea of having to spend hundreds of dollars to get the gun fixed. :-( I'm willing to put time, money & effort into the gun...I just was hoping that it would start off being a good shooter & I'd take it from there.

[TRAP55]

Be on the safe side and have the headspace checked. But what you describe sounds like "sticky bolt syndrome", caused by cosmo and/or laquer from steel cases in the chamber. Get that 20ga brush in there chucked in a hand drill, and give it a liberal flushing with some carb cleaner.
There's also been problems with some of the FN MilSurp ammo, something with the brass alloy in the cases and the way it expands. Clean the chamber and try some different ammo.

[Indian Creek 1]

Maybe lug setback.

[jeanp1948]

I had to take the bolt apart and place in Carb cleaner can overnight. Then clean thoroughly with Gunk/kerosene mix. Wipe with light oil afterwords.
The second step is not popular with many gun owners but I use it because it works great. Place your receiver (minus stock and all wood) in a padded vise. Have barrel tipped down in old can. Then use a small steam cleaner to clean starting at the breech works and then straight down the barrel. You should see green crud, black crud, and bit of various metals drip out of your barrel. Then clean entire receiver in the same Gunk tank mentioned earlier. This was the only way I got my M44 Mosin to work properly after firing corrosive ammo. Try it! You got nothing to lose!

[Mark]

The problem may be a need for lubrication.

A mauser 98 bolt cocks on opening, and the cam on the bolt that lifts the striker needs lubrication. Not a lot, but something.

If you cleaned the rifle, and left it bone dry, you may have started a little galling on this surface that would make opening the bolt stickey. I'd look at this before bothering a gunsmith.

Correct headspace is always an important issue, but there are other things involved in making a Mauser run.
Mark

[polishshooter]

EXCESSIVE headspace could also cause the same problem, hard opening is just one of the symptoms, BUT you should be able to see signs of excessive pressure along withe that, such as (first) extruded or flattened primers, or bulged or cracked cases.

I'm a little worried, because if the problem was a "tight chamber," you should have problems CLOSING the bolt as well, not just OPENING. You said it "feeds" them into the chamber well, didn't you?

It COULD also be the tight chamber or crud in the chamber/extractor recesses...sometimes these problems are a combination of issues over time.

One of the main problems with Mosin Nagants having that problem is a lot of use of lacquered steel cases, with some of the lacquer coating the chamber if a round is left chambered in a hot chamber for any period of time.

While I have NOT heard of that same problem with Mausers, mainly because I 'm not sure there is all that much lacquered steel case stuff available to shoot in them, it COULD be the same problem...

The trick with Mosins is to take that 20 gauge swab, put it in one section of an old cleaning rod, chuck it in a drill, and put a little valve POLISHING (NOT "lapping!") compound on it and zip it in and out one time. If it comes out green, then keep at it until it comes clean, then try it.

Remember, you are POLISHING, not REMOVING metal. Polishing compound is like 2000-2400 grit or smaller, LAPPING compound is like 800 grit. You can get it at any auto parts store, just make sure it's POLISHING.


Then the next thing is to get some picks and REALLY clean all the recesses in the chamber area.

Finally, check out your cases, to see if your extractor head might not be digging into the backside of the case head. I have fixed this problem before by changing extractors, but it usually is tough closing as well as opening if this is the case as well....





And guys, SEE??? I CAN give advice on crappy worthless Mausers WITHOUT letting any of my bias against them show through...

(GOSH I love RIMMED rounds in old military rifles though.... )

[Indian Creek 1]

I'll say it again, you might want to check for locking lug setback. After years of firing the locking lugs can push back a groove in the receiver rearward of the lugs in the firing position. the cartridge will chamber with no problem but when firing the brass will expand as the bolt moves back into this groove . As the brass is now longer it will not allow the lugs to rotate out of the groove easily.

A.J.

[polishshooter]

Yeah, Indian, that could be, I've heard that can happen with Enfields but I haven't heard it on Mausers. But then again the Enfield issue I don't think it actually sets back in the reciever is it? Just the bolt head sets back I think.

Doesn't that take soft steel in the receiver to more or less elongate the lug recesses?

It's not something you can fix just replacing the bolt head either, is it?

And isn't in effect what's happening is it's allowing excessive headspace?

[Indian Creek 1]

Polish most of these old mausers have seen extensive use around the world and a lot of them were rode hard and put up wet. The receivers on the 98 mauser is heat treated giving it a surface hardness of only a few thousands of an inch. Wear from from an unknown amount of use through the years takes it's toll. Excessive headspace ,worn down surface hardness , or firing hot ammo all takes its toll as it does on any firearm. When setback occurs locking lugs can be lapped in but the receiver then needs to be reheat treated. You are right about headspace, when the lugs setback it increases headspace considerably. You may get a good reading with go/no go guages but once the lug drops into the recess from the setback you have excess headspace.

A.J.

[Light Coat]

It's a naughty thing to say; but, dry fire and see if your bolt has trouble opening. This will determine your cam function. If you pull back on the handle while opening on a different attempt you may determine if your lugs have nested. Use a caliper on your fired cases start at the truncation at the rear of the neck and work your way back to the extracting collar and compare the measurements with an unfired case. You can also take a chamber mold if you like; as long as you use a good release agent you can use about anything to take the mold. With the availability of gages for the 8mm I would use a gage wrather than a mold.

If you can't find anything else wrong you may want to dissassemble the bolt and check for wear or a notched firing pin.

[CCubed]

Wow. Eventually this got a lot of responses. Here's the deal.

First of all, I bought myself a set of headspace gauges for the 8x57 Mauser. My headspace checks out fine. No problems. Closed on "go". Didn't close on "no-go" or "field". So, I think I can rule-out headspace as an issue.

I cleaned out the chamber with a 20 gauge brush and swab & Hoppes #9. I think that did something, 'cause when I fired it, it was much, much easier to open the bolt. Now, it's still not perfect, but I suspect that the chamber's just dirty.

As for the rest of the issues brought up above, I'll be sure to look into them. Unfortunately, I can't fire my guns for extended periods of time, since I'm at college. I plan to go home soon & take the Mauser, give it a good going-over once again, and then try shooting it. If I've still got issues, then I'll start checking into all the possibilities mentioned above.

Thanks for all the advice & tips, though. I really appreciate them. Keep them coming. You might be helping someone else out too.

[Scalp Hunter B/7/17]

Originally Posted by CCubed

I hate reposting stuff, but I wasn't getting many hits in the "technical advice" (or whatever it is) forum section. Anyway, here's the deal.

I took my 98k out the other day, after cleaning it. I got most if not all the cosmoline out of it, and did a good job cleaning the barrel. It looked fine. I took it out and put some lightly corrosive, FN 8mm rounds through it. From the get-go, I knew I had a problem.

I had the hardest time lifting the bolt handle up, to recock the hammer and open the bolt. Some thing's wrong. The weapon cycles these rounds fine; I can't find anything wrong with the bolt. The barrel and the chamber seem fine - no serious or deep pitting, or anything like that. These rounds fired fine through my M48 Mauser.

Now, this particular bolt doesn't have quite the "snap" which my M48 bolt does. When I have the safety completely off and I open my M48 bolt, it snaps back a bit. The bolt on the 98k doesn't do that, at least not as well. It does seem worn.

My concern is that the one and only person who responded to my post in the technical forum said that he thought it could be due to problems with the chamber, etc. Honestly, I'd rather have problems with the bolt; they're easier to fix. If, however, I'm having, let's say, headspace problems, can it be fixed and if so how? (I know that a gunsmith would have to do it.)

I would take it to a gunsmith to analyze the problem since, as you observe, it'll require him to make any repairs, anyway. The combustion and heat could be warping a fatigued section of the bolt or its slide which returns to its formed state after cooling. Eventually, failure could be pretty nasty.

My first Mauser is an inherited Mod B Sport with tandem trigger. Because the set trigger would snap if it were looked at too hard, I was concerned that other components were similarly worn, so I had it inspected before I fired it. The gunsmith disconnected the hair trigger, tested the chamber, and bolt - nice job but I haven't bagged a deer with it yet. RJS

[CCubed]

Well, here's the deal, everyone: End of story, the gun shoots fine. It was just crud in the chamber. I might decide to take it to a gunsmith, but I really doubt it. The headspace checks out, the problem's gone & it shoots like a charm, so... But thanks for all the responses.

[TRAP55]

It was just crud in the chamber.

Told ya so. Glad you got er fixed!