My 8mm Mauser has a somewhat sticky bolt.

P

Prothe2nd

New member
Trying to get to the root of a problem. Every now and then my 8mm k98 Mausers bolt will refuse to open. It takes a heavy stick and some hard raps to get unstuck. Brass is not deformed in any way.
Little info on firearm, 1944 k98 Mauser, chambered in 8mm. Sometime after WW2 was sporterized with a hunting stock, new sights and new safety. The ammo I've used in it is Hotshot steel cased 8mm and yugo surplus 8mm. Can anyone tell me why it sticks, and possibly how to fix it, whether it's the bolt, the ammo, or something else. Any info appreciated.
 
Use better ammo. The cheap stuff ain't worth it, IMO.

Also, make sure that your cheap ammo is not corrosive primed.

If you are not sure, scrub the bore with very hot soapy water to remove the fouling, then follow usual cleaning methods.
 
Steel cases are not the ideal metal for cartridges cases.

If you mounted a scope on it, check that one of the base screws in not protruding too far into the receiver.

Otherwise, don't use cheap ammo. That's my advise.
 
I'm not scared of corrosive ammo, and I don't clean my guns with water. I use hoppe. I disbelieve the fact you have to pour soap, water, and window cleaners down your firearms. Refer to some videos by a gun channel on YouTube called imperialfragments
 
Get some brass cased ammo and shoot through it. Then examine/measure the fired cases and make sure the chamber isn't oversized. I have a mosin like that, brass cases come out easy, but steel cased stuff doesn't want to at all. Just my ssuggestion, good luck.
 
disbelieve all you want, oil and regular bore cleaner will not remore the corrosive primer material. a water based cleaner will dissolve the corrosive material and wash it out of the bore. if you shoot corrosive primed shells and don,t get all the primer residue out you risk a ruined bore. eastbank.
 
Every now and then my 8mm k98 Mausers bolt will refuse to open. It takes a heavy stick and some hard raps to get unstuck. Brass is not deformed in any way.
.....
The ammo I've used in it is Hotshot steel cased 8mm and yugo surplus 8mm.
Click to expand...

It's an ammo problem for sure. A lot of the yugo surplus was originally machine gun ammo, and I haven't seen any lots on the market not from the late 70s and early 80s so odds are you are getting some pretty interesting pressure situations that aren't conducive to brass springback. The steel ammo, steel doesn't have much springback at all, much more common to get stuck cases with it.

Jimro
 
My Mosin 91/30 had a similiar issue. Mosin's are notorious for sticky bolts but I switched from the lacquered coated steel case stuff to the zinc plated MFS and Silver Bear, I haven't had a bolt issue since.
 
I've heard that the HotShot 8x57 ammo is on the hot side. I do know that some of their other ammo is really "hot". It sounds like you're getting an occasional overload that sticks your bolt.
If your bolt lug recesses have a tiny bit of setback or peening, the extra hot loads will exacerbate the "sticky bolt lift". Once those steel cases are fully expanded, the slight "re-sizing" that occurs when the bolt cams open against the set-back lug recess can cause the initial "sticky lift" feel(even w/o an overload).
Regarding the use of Hoppes #9 to clean after corrosive primed ammo: I found that some 8x57 ammo that I'd been shooting for about 2 years was considered "slightly corrosive"(something like being "slightly pregnant"). I'd been cleaning well with Hoppes #9 immediately after shooting and had zero corrosion problems. I can't recommend the practice BUT it worked in this specific case.
 
I have hundreds of surplus WW 11 German 8x57 ammo and most of it is steel cases I figure they could not get brass anymore. never had a problem. absolutely no reason to use expensive ammo being maybe the chamber has to be polished with a brush wrapped in steel wool attached to a drill. these are combat rifles that do not have tight match chambers as everyone knows
 
The Hotshot stuff has a reputation for being borderline on dimensions, some guns won't even chamber the stuff.

Not so with the Yugo surplus, that I have ever heard.

I'm not scared of corrosive ammo, and I don't clean my guns with water. I use hoppe. I disbelieve the fact you have to pour soap, water, and window cleaners down your firearms. Refer to some videos by a gun channel on YouTube called imperialfragments
Click to expand...

Well, some people disbelieve the Earth is round. Doesn't make it any less true.

The corrosive part of corrosive ammo is salt. Salt is washed away with water, but not as well with other cleaners.

RE Hoppes, one of the (many) previous times this came up, a guy on Calguns ended up calling Hoppes to get the straight answer. Which was: "No"

The old formula worked fine, the current formula, not so much.

Hoppes No9 plus is formulated for Black powder, and should work fine on corrosive primers. http://www.hoppes.com/bore-cleaners/no-9-plus

That being said, unless you shoot black powder, buying a special solvent just to do the same job as water you get from the tap for free, seems silly.

It is a crying shame the old Surplusrifle.com site is gone. There was an excellent test on there, testing pretty much every commonly available solvent on removing salts, Most of them didn't, and his pieces of test metal rusted nicely.

Luckily, it looks like the test is available on the wayback machine:

https://web.archive.org/web/2007070...usrifle.com/reviews2006/alittlesalt/index.asp

It is 4 pages long, and worth the read.

The British Commonwealth troops even made funnels for pouring hot water for bore cleaning. After a trip to the range, they would put the water on for tea, and bore cleaning.

A quick Google search turns up these:

British funnel:
http://www.milsurps.com/enfield.php?pg=ti21.htm

Canadian Funnel:
http://denner.ca/weapons/GunAccess/index.html

To kill the salts after shooting corrosive ammo, I use hot tap water, followed by a good squirt of WD40 to displace the water, followed by a shot of Break Free and one patch.
 
Check the length of your firing pin and the size of the firing pin hole in the bolt face. If the ammo is hot, the primers may be "Welding" the pin in place. An oversize F/P hole will give the same symptoms.
 
"...soap, water, and window cleaners..." Hoppes doesn't clean out the salts of corrosive primers. Neither does soap or window cleaners. Hot tap water does.
YouTube is where Bubba lives. It's worse than Wikipedia.
Anyway, a sticky bolt is one of the indicators of excessive pressure. Change ammo. But check the headspace too. 1944 Germany wasn't a great place to be making rifles with all those guys dropping bombs on 'em, the QC was lower.
That Hot Shot ammo(manufactured by Prvi Partizan) is non-corrosively primed anyway, but corrosive priming is not the cause of sticky bolts. It is, however, made for Century Arms and that alone makes it suspect.
"...Surplusrifle.com site is gone..." Not quite.
https://www.dropbox.com/sh/kh9guf4wvgqt8o5/AADQEHpHP43p-QOiMKJajVKra?dl=0
 
That Hot Shot ammo(manufactured by Prvi Partizan)
Click to expand...

No it isn't. If it was, it probably wouldn't suck.

Privi Partisan is in Serbia, the Hot Shot 8mm is made in Romania.

On the other hand the Yugo surplus most likely was made by Privi Partisan, it was run my the Yugoslavian government, when there was one.
 
Neither does soap or window cleaners. Hot tap water does.
Click to expand...

Well, factually wrong, but I agree with T.O'heir's point.

The main ingredient in soapy water or window cleaner is...water. Hot water will dissolve salts marginally better than cold water, but any aqueous solution is going to dissolve potassium chloride (the main salt product from potassium chlorate based primers).

The "hot soapy water" tradition comes from cleaning out black powder barrels where some form of lubricant is used either in the bullet (that's what the "grease grooves" are for) or in a patch over a round ball. Of course the black powder residue leaves a lot more stuff behind to get rid of, plus the lube.

The window cleaner comes from the mild ammonia content somehow being favorable for copper fouling removal in addition to washing away the salts. Yes it can work, but I don't bother with window cleaner as leaving it in the bore long enough to attack the copper isn't going to do any favors for bare steel.

I'm not convinced that either hot soapy water or window cleaner will work any better than plain old water. And the reverse is also true, odds are plain old water isn't going to work any better than the other two options.

Jimro
 
The locking seats in the receiver may have taken a set back due to poor heat treatment/metallurgy or excessive use of hot ammo.
 
ONLY some rounds. SOMETIMES he has to beat the bolt open with a stick.

This indicates incompatible ammo (as individual cartridges, not the entire batch/lot or everything made by that brand.

If it were a mechanical rifle problem, it would be a constant or near constant thing. According to the OP, it's not.

He's shooting the cheap stuff. NOT high quality, CONSISTANT ammo. That costs more.

The most likely explanation is inconsistency in the pressure of the ammo. Some individual rounds are hitting (or passing) the level your rifle likes. Cases get "welded" to the chamber walls (insufficient springback of the case)

The cam action of the bolt when the handle is lifted pulls the case a small amount backwards, breaking any adhesion between the case and chamber walls. This is "primary extraction".

When the pressure is too high (and this is a matter of the specific rifle and cases, more than what the books list as "max") the case sticks, resisting the movement that must take place because of the camming action of the bolt being opened, and this resistance is felt as a "hard" "sticky" bolt lift.

And when its really well stuck, you can't open the bolt by hand, and must use additional means (the stick, or a mallet, etc.)

There are other reasons for hard bolt lift, but if it is something mechanical causing it, it is usually constant or consistently intermittent, not random.

Random is nearly always the ammo.
 
I'm not convinced that either hot soapy water or window cleaner will work any better than plain old water.
Click to expand...

Window cleaner is a no go with me. I have been tempted, but never fell into that trap.

I am convinced that very hot soapy water works quite well. The reason for the very hot water is it heats the barrel and then what does heat do to water?

Been doing it for close to 55 years with BP guns and when I was a pup all I could afford was a box of 100 yds of Greek made ammo for $5.00 with corrosive primers.

My mentor taught me well as I am still shooting that old Mauser.....and the bore still looks as good as it did back then.

Also, my black powder barrels are shiny enough to look like they are mirror quality.

Very hot soapy water. Then delve into a normal cleaning routine.
 
You must log in or register to reply here.
Back
Top