Mauser barrel is STUCK!!

[mwells72774]

Its a 1912-61 7.62x51 chilean. Tried soaking in penetrating oil, PB blaster; tried a cheater bar; even tried heat (377deg according to uncle who was in charge of the heat, colored the action and didnt budge). Any ideas?

[F. Guffey]

I do not have trouble with removing barrels, when stuck I use a press, no wood blocks, no rosin, I have had barrels 'so stuck' I could set the wood blocks on fire, and still, no barrel hold. Action wrench? I also have a 4 foot cheater for the action wrench. Then there are hammers and sudden shock, the ears on the old action wrench are pounded round.

I understand not everyone has access to that much equipment, still I wonder, how does a barrel that is stuck get removed with less.

F. Guffey

[mwells72774]

i've got some aluminum barrel blocks from a good friend of mine. even put some rubber in there for more traction. Nada. action wrench isn't doing crap. thinking I might be better off with a crescent wrench.

[F. Guffey]

Then there is the other problem, the 7.62mm51 is NATO,NATO did not exist in 1912. I have never removed a barrel from a Chilean Mauser that resembled anything that fit when chambered in 308W or 30/06. I am not talking about contract rifles made for Chile.



F. Guffey

[F. Guffey]

I have 48" pipe wrenches, care must be taken if the purpose is to save the barrel and or the receiver, I have friends that claim they have crushed barrels with pipe wrenches, I have to take their word for the event, I was not there.



F. Guffey

[mwells72774]

it was originally a 7x57, but in the 60's ('63 on mine) they were rebarreled with surplus M1903 Springfield barrels cut down to mauser profile and rechambered in 7.62x51 NATO

[hooligan1]

I removed the barrel from my Turkish Mauser: Used quality penetrating oil,( P.E.N.) and fill the ring where barrel meets reciever. Then I take a 3 lb hammer and smack the muzzle straight on 5 or 6 times, refill ring with penetrant. Let set overnight check and see if penetrant has dissappeared, if so we're in business if not repeat earlier mentioned steps. Pipe wrench on fattest part of barrel and action wrench engaged with action resting on floor, I place my right foot on pipe wrench (18 inch Rigid) and the action wrench backed on floor, I used a propane torch and evenly heated the thread area of action while increasing pressure with my foot and bam, it worked so fast the reciever could be handeled with bare hands.

[HiBC]

On original military Mauser bbls,there is no shoulder contacting the forward face of the receiver ring.
As this is a retro barreled rifle,you likely have a shoulder bearing on the front face of the receiver ring.
You can run a lathe parting tool about .020 ahead of the receiver ring into barrel,approx down to the minor dia of the thread.This will relieve any preload on the forward receiver ring.

One way to warm it up is dunk the receiver in a Presto Hot pot of peanut oil.

Then you can get everything over 300 deg with out hot spotting anything.A heat gun is another option.

If you get yourself a can of freeze spray,when you have everything hot,wrenches on,torque applied,no luck...try shooting freeze spray through the bore while you have full torque on the bbl.

[PetahW]

.

As a last resort, the barrel can always be cut off even with the front face of the receiver and most of remaining chamber end bored out from the front.
The remaining bbl threads can then usually be picked out of the receiver threads.




.

[4V50 Gary]

Breaker bar over the wrench.

[Dixie Gunsmithing]

There is one other trick to try before getting drastic. Mount it in a vise, with a wrench on it. Then, you need to heat the frame, while cooling the barrel. To cool it, you need a small bottle of CO2, and a hose with something to direct it into the chamber of the barrel, like a small piece of aluminum or copper tubing, bent and inserted into the hose end. After the frame is heated, crack open the valve on the CO2, and let a small stream flow through the barrel, from the chamber, which will chill it and shrink it. Next, try to torque the barrel off.

[Gunplummer]

First Mistake: Don't use a vise and aluminum jaws. You are not working on an M-16. Use a solid split block with split brass bushings bolted to a bench. Second mistake: Using a receiver wrench without shock treatment (A very large hammer). Don't bother with internal receiver wrenches. The poster with the shoulder relief info was right too. If you have a lathe (Or mill), you can cut off the barrel and CAREFULLY work the chamber area out. The worst rifle I ever had to disassemble was a Russian bolt action. I eventually milled flats on the chamber area of the barrel for the bench block to get a grip. It sounds as if you are not equipped to deal with this situation. That is O.K., it is a good learning experience. Now you are getting an idea why gun work costs so much.

[mwells72774]

well, got home today and out to the shop with me.

put the barrel in a light vice in the alum. blocks I had with some powdered chalk. grabbed a pipe wrench and 2 small rectangles of brass. it took next to no pressure and pop, off the barrel comes.

now, the issue is getting the green mountain barrel on. it gets 2 threads in hand tight and from there, its tough. haven't tried to torque down on it.

has anyone else installed a green mountain F54 contour barrel before?

this is my first rebarrel project, so I'm asking a of questions.

[Clark]

Here is a 2 minute video of me getting an old rusty barrel off with 540 foot pounds of torque.
https://www.youtube.com/watch?v=YOjYro4w0Bc

[Gunplummer]

I can believe that!

[wpsdlrg]

Congrats. Now that you've got the old barrel out.....a word about installing the new barrel. First, check the threads on both the new barrel and the receiver. Especially the receiver. Unfortunately, the old technique of fitting Mauser barrels with a "crush fit" tends to damage the receiver threads (compresses or "crushes" them). "Crush fit" is a bloody STUPID technique - period. Ignorance, plain and simple.

The reason you are having trouble in screwing the new barrel into the receiver is probably that the threads are damaged. You MAY need to obtain a suitably sized thread chaser and work over the receiver threads. After checking everything carefully, try this first: heavily lube the barrel threads (even a thin grease for this purpose will work)....then slowly screw it into the receiver, a bit at a time, under more than hand pressure. Stop often, when it hangs up and back it out. Check for any debris or bits of shaved metal, etc....clean, re-lube, then try it again. Working this way, you MAY be able to chase the receiver threads, by using the BARREL threads. Understand, this is to chase the receiver threads....and get the barrel TEST fitted. It is NOT final fitting of the barrel - so, if you get it all the way in this way, DON'T just torque it down and decide that you are finished. This technique MAY not work - if the threads are too buggered. If they are, then a thread chaser or actual re-threading may be needed. BE CAREFUL - if your receiver threads are too damaged, you could damage your barrel threads to match - not a good thing.

Once the issue with the threads is solved.....let me say this about the final install of the new barrel. PLEASE DO NOT do the stupid "crush fit" technique ! It is both unnecessary and will simply cause the same problem all over again. The new barrel only needs around 75 lb/ft. or so, of torque. (The barrel will not "shoot loose" with this much torque.) What you want, for good tight headspace, is to ensure that the barrel face bottoms on the inner torque ring. There is NO need for the outer barrel torque shoulder to contact the receiver face, before that is achieved. That is what produces the "crush fit". So, for god's sake, cut the outer barrel torque shoulder back enough (or the face of the receiver) so that they only barely touch, when the barrel is torqued in place. Then, damage to the threads will be avoided - and future re-barreling will be easy, as it should be.

[Clark]

If I plug in the Mauser info
http://www.futek.com/boltcalc.aspx
I get 500 + foot pounds recommended, 750+ foot pounds max

Barrel threads are very different. We get all the clamping force we need for accuracy with a few foot pounds. I have shot good groups with the Mauser barrel on finger tight.

The reason we put 75 foot pounds of torque on a barrel is so that it will not come loose.

There is some controversy on the internet as to why Remington is putting glue like goop on the Rem700 threads.

[wpsdlrg]

Clark,

The bolt calculator linked above assumes a solid bolt - NOT a hollow barrel (tube) and hollow receiver - which are considerably weaker than a solid bolt and suitable nut of the same diameter. So, in this circumstance, the bolt calculator application linked is not applicable (N/A).

(I'm sure that you already know that - and just used it as an extreme example.)

Just stating the facts - in case anyone ELSE is confused about that.

Obviously, I completely agree with your second and third points. Well said.

Finally, I assume that Remington applies thread dope to it's barrel threads simply as a failsafe - that is, to try to ensure that their barrels won't come loose after many years of use and abuse (and possibly subject them to dubious complaints about "quality" or lawsuits from ignorant or opportunistic people). In other words, probably just as an extra margin for "CYA" purposes. Thread dope is useful for one purpose, anti-corrosion. Perhaps they assume that, for a firearm that may be used in the field under all sorts of weather conditions (and for many years), it is a good idea.

In truth, I have always done the same thing. After seeing the rust that can develop and is very often present on old Mauser barrel threads....I've applied thread dope on every one of the 14 or so Mausers that I have rebarreled, over the years.

[F. Guffey]

“now, the issue is getting the green mountain barrel on. it gets 2 threads in hand tight and from there, its tough. haven't tried to torque down on it.

has anyone else installed a green mountain F54 contour barrel before?”

Again, I have 4 Chilean Mauser receivers, I have no less than 30 Mauser barrels, I do not have a Mauser barrel that will thread into the one of the of the Chilean receivers. The Chilean receivers barrels were replace in 1934 to 30 cal. Again, the receivers are not from contract rifles. There is an interference between the threads in the receiver and barrel, the barrels that were removed were shot-out and a few had case head separation with the case body still in the chamber. Once the barrels broke loose nothing got easier, meaning nothing got easier until the barrel was almost ready to fall out. I cut chambers off of the barrel and then used them as chamber gages.

Mauser from 8mm57 to 30/06: My Chilean Mauser receivers were modified, the box was longer with a longer floor plate. The modification caused concern, metal was removed from the receiver, it was believed the metal removed weakened the receiver behind the bottom bolt lug. I used one barrel to test fire all 4 receivers, nothing suspect. I paid $25.00 each for the (almost) complete rifle, it took me 2 + years for Hoosier Gun Parts to find 2 long floor plates.

F. Guffey

[wpsdlrg]

OK. I can say that I think that I've never re-barreled a Chilean Mauser.

So, what is your point ? I mean, as regards assisting the OP in his re-barrel project ? So stipulated - Chilean (non contract) receivers are different than other Mauser receivers. Then, how is he to proceed ?

I assume that you are asserting that the threads in the receiver vs. the barrel threads, are substantially different. Yes ? If so, then re-threading the receiver may well be mandatory (or the barrel). If not practical, due to a large difference in the thread patterns, then he might have to start with a barrel blank...and have it custom threaded to fit. Why not just SAY that - if that is what you intend ?

[Clark]

I was processing more than 50 Mausers once [5 per carton from Century], and guys would come over and I would have them pull the rusty old barrels.

I would have them sit on the cheater bar while I hit the action wrench with a 20 pound weight. No movement.

Then I would put some Kroil into the thread joint.
Wait 10 minutes.
I would then have them push on the cheater bar again... and it comes off with half the force that had not worked 10 minutes earlier.

All the guys I subjected to this magic trick went out and bought Kroil.

[Hawg]

My gunsmith told me once that old British .303 barrels were the worst. He'd lock the barrel down in a vice and use an 8 ft. cheater on the action wrench.

[F. Guffey]

wpsdlrg,

It’s OK, I doubt your are hard on yourself, but, just in case you are, don’t be. The OP said this is his first build, I tried to prepare him for his first build ‘IF IT WAS A CHILEAN MAUSER’ so? Someone needs to ask him what receiver he is trying to build.

Then the link, the one you knew Clark knew did not apply to this thread. Going straight to the 700 foot pounds of torque. The shank of the barrel is to short to apply those kind of numbers, even if it was solid. Then there was your editorial on “CRUSH” and “DON’T' YOU BELIEVE IT”. I will not give you the benefit of knowing, the Masuser barrel face bottoms out on the C-ring torque surface in the receiver. After making contact the two surfaces do get closer, the surfaces can gall, slack between the threads can be removed but the two mating surfaces do not get closer. That brings up the shoulder at the end of the threads, I secure the barrel then measure the gap between the front of the receiver and shoulder at the end of the shank, I want the shoulder on the barrel to make contact with the front receiver ring after the barrel face makes contact with the C-ring.

After the barrel face makes contact with the C-ring I want .003” gap between the front of the receiver and shoulder at the end of the threads. I use the most humble and modest of all tools, I use the feeler gage, also know as the thickness gage. Same for the M1917 and the Springfield 03 type rifles.

The Mauser (98 type) barrel bottoms out, back to the link that has little to nothing to do this thread is about. A bolt being torqued was never designed to be torqued when bottomed out, the best way to shear a bolt with torque is to bottom it out then mindlessly continue to torque.

Then there are the other barrels like the Springfield and the Enfield M1917, the barrel seats against the front receiver ring and shoulder at the end of the threads. Difference? Yes, the big difference is square threads, when it comes to thread design there is nothing stronger than square threads, after square there is acme, then there is that story about Eddystone using steam at the rail yards to secure barrels, again, once the two mating surfaces makes contact there is not much chance the two surfaces are going to get closer, that leaves pulling threads and creating stress on the receiver. I have Eddystone receivers, I have one that is cracked/split. Back to two surfaces getting closer, if the Eddystone was indexed and the builder knew how to deterring the distance the barrel had to be torqued to align, the amount of barrel rotation to torque would not have required steam power. When they built the M1917 no consideration was given to removing the barrels, we needed the rifles, we knew the slack was not going to be taken up by Springfield.

F. Guffey

[mwells72774]

The barrel finally broke free.

After some modification to the threads, they tighten all the way to the c-ring and shoulder meets front of receiver at the same time. Had to sand the threads on the barrel down to 55 deg.

[F. Guffey]

mwells72774, some of these guys would pass out if I claimed to have cut the threads down on a M1917 barrel, the sank was straight but the threads were cut on a tapper, good to hear back from you. Now? Comes the part were you determine the length of the chamber from the shoulder to the bolt face (everyone else calls it head space).

F. Guffey