Loose barrel

[Bavarianbrit]

Hi,
A pal of mine shot ten rounds at the range with very good accuracy then today he went out on a hunt in Germany and the recoil was noticeably hard and before he could take a second shot at the animal he saw that the front sight was offset at 90 degrees off from the vertical so he stopped shooting, the rifle is a K98 and was fully engraved by a master gunsmith but it was bought by him as in used condition. .308 PPU B-062 bullets reloaded into Barnes cases with 43.0 grins of H4895 is what he was using. He had to push the bullets slightly further into the Barnes cases as they would not feed up from the mag into the chamber otherwise. So the barrel has unscrewed itself somewhat, has anyone heard of this ever happening? I have not.

 

[webley701]

I’ve witnessed it happen on a 6mm PPC benchrest rifle where the owner had switched barrels & either forgotten to apply the final torque or hadn’t applied enough.

Barrels on Mauser actions are typically installed with much greater torque than BR barrels - gunsmiths are far more likely to complain at the difficulty of removing rather than them being too loose. For one to ‘undo’ in use is bizarre & you’d have to imagine it wasn’t properly installed rather than had come loose (through vibration etc).

 

[Bavarianbrit]

That's my thinking too. Waiting for more feedback.

 

[palmer_mike]

Seen it happen on a proof gun where I used to work.

 

[kenbro]

I’ve had a barrel come loose in 2009 if I remember correctly.
Was in the field and for whatever reason leaned my rifle against something and felt a movement as I let go of the barrel.
I was able to take the barrel out by hand.
Rifle had recently been built so obviously proper tightening hadn’t occured.
No harm done.
Ken.

 

[HonestJohn]

Poor threading work without sufficient bearing surfaces to ensure torque would hold it.

Chances are when done up tight again the sights might over run the vertical and it will look like shjite. So the only solution to aesthetic also make this work is to re-torque it up with (shock) a strong binding agent on the threads

 

[billgatese30]

Haven't seen it on a barrel, but have seen it before with a freshly machined piece (warm ~20ish degrees C) which is was being threaded into a cold female thread which came in from a cold warehouse. Once the temperature equalised on both parts they needed re-torquing.

 

[Bavarianbrit]

I just spoke to him again, he has used the rifle for the last 15 years with no issues. The shot he took was a 140 metre one on a chamois near Freiburg. I am waiting for the whatsapp video as he says he can unscrew the barrel all the way out by finger pressure alone. The rounds he has left all measure to an OAL of 68mm. My GRT programme says that all over 66.7mm long will be OK on that loading.

 

[Bavarianbrit]

It appears it was 43.0 grains of IMR4895 so still well within the safety levels.

 

[Bavarianbrit]

The only thing I can find on the net from self proclaimed gunsmiths is that a RH twists tighten the barrel with each shot and a LH twist forces the unscrewing. Or was it the other way around? Who would have thought of that one?

 

[kenbro]

The only thing I can find on the net from self proclaimed gunsmiths is that a RH twists tighten the barrel with each shot and a LH twist forces the unscrewing. Or was it the other way around? Who would have thought of that one?

Suppose it depends which way the rifling goes?
Kb.

 

[Twodogs]

Lee Enfield barrels have a left hand twist to their rifling, never heard of one ever coming loose.
Not correctly tightened in first place would be my guess. Would not necessarily show at any particular point in time.
As to the barrel has unscrewed, when tightening again check for verticality of front sight, if rifle has one of course, and Cartridge Head Space.

 

[Bavarianbrit]

It will be off to a local smith of his with years of K98 experience under his/her belt I would suppose.

 

[Bavarianbrit]

He spoke to the smith and his reply was that it is not so uncommon. Sauer appear to have issues with this. Every day is a school day.

 

[kenbro]

You’d think they’d have a cure by now!
Kb.
Ps. They will have cures, just don’t want to use them.

 

[Bavarianbrit]

A pin run through a tiny hole in the receiver underneath left to right to just contact say 1mm the tip of the barrel thread would stop that happening.

 

[MarinePMI]

A little bit of rosin in the threads will cure that as well...IIRC, that is what Mauser used when they built many wartime 98's...

 

[Bavarianbrit]

When/if it is screwed back up tight and the barrel turns out to be still OK I assume it will have to go through proof testing again. Could be the time to go for a fresh barrel he has almost 500 through it and the gunsmiths cost will be there with either solution.

 

[Ronin]

Mauser actions are case hardened, they do not take kindly to being over tightened - they usually lock up on the inner action face rather than the normal outer diameter of the action face

One would normally cut the barrel so there is .001/.002” gap on the OD of the reciever face - with contact as I said only on the inner ring

It is a not so uncommon occurance that barrels come loose - I’ve seen factory barrels loosen on a few rofles - usually where moderators have been left on and the end user has put a oil filter wrench or similar on the mod and loosened the barrel

I’ve never seen it on a Mauser action

It’s possible if it has had a replacement barrel fitted that whoever tightened it only did so nominally

If the owner has a action wrench it’s a simple task to spin back on and re torque either to the witness marks which are usually on the underside of Mauser 98 pattern barrels or to something bettween 60 and 80 ft lbs

Check headspace with a set of guages and away you go

I’m not sure proof is required - has there been any alteration to pressure bearing surfaces ?

 

[Bavarianbrit]

Not that I am aware. The owner has not got an action wrench but he is very interested in gunsmithing as in he has a decent workshop and did very many visits to his local gunsmiths shop where he whiled away hours asking questions about all the basics like filing correctly he has got a German gun dealers licence. Sadly this master gunsmith who was trained at Suhl died a couple of months ago at 57 years and that business is now on hold until the wife can hire a professional to clear/sell/destroy the many hundreds of long and short guns that are still in his workshop. He was not a retailer but he specialized in buying up and exporting deceased German hunters equipment to eastern Europe.