Question on barrel replacement ...

[G.T.]

Hi Guys, I seldom have to have a barrel removed, but in trying to be a'bit more self sufficient, I have delved into a few removals and so far so good, My equipment protects the receiver well enough, but, my barrel vice set up using lead shims, doesn't seem to be the real ticket... No galling, but it's hell on the finish... So, what's a guy to try next?? ... I want to be a bit better prepared to put a nice barrel back on... Soooooo, how do you guys hold a barrel and how much force.... ... Best to all, til...lat'r....GT

[Edward Tinker]

don't know, I have had 2 or 3 barrels done and had Hugh and Tom do them for me....


Ed

[G.T.]

Hi Ed, yes, ........I'm kinda getting outta my range here a'bit, but so far so good, I'm thinking screwing one off is a bit easier then twisting one back on correctly... I'm also thinking Art B. is as good as they get for knowing how... ... He's as good as they get on this part of the game... best to all, til...lat'r...GT

[Hugh]

Originally Posted by G.T.

Hi Guys, I seldom have to have a barrel removed, but in trying to be a'bit more self sufficient, I have delved into a few removals and so far so good, My equipment protects the receiver well enough, but, my barrel vice set up using lead shims, doesn't seem to be the real ticket... No galling, but it's hell on the finish... So, what's a guy to try next?? ... I want to be a bit better prepared to put a nice barrel back on... Soooooo, how do you guys hold a barrel and how much force.... ... Best to all, til...lat'r....GT

GT,
Are you using powdered Rosin between the bbl and the lead shims? This is absolutely necessary to prevent the barrel from slipping!
Hugh

[G.T.]

That's probably what I'm doing wrong.... makes sense now! Thanks Hugh, til...lat'r....GT

[G.T.]

Hi Rick, Good to hear from you... ... I learned about the clean part first time... then I learned about too much lead... then I learned about too many bolts on the barrel vice, don't need four... Then, I learned about bending the leverage bar... Then, things started to get better.... I now see where the rosin is 100% necessary, and probably my main reason for difficulty... The tape idea sounds great and I can see when using metal blocks or shims, something like that is needed... I'm going to re-read, and re-read again your post and make sure I'm taking advantage of all info available.. Thanks Rick, best to you, til...lat'r....GT

[John Sabato]

The last time I needed any powdered resin (1987) I just went to the local bowling alley and bought one of those hand sized burlap resin bags that bowlers use to give their hands some purchase... There is enough powder in one of those bags for many barrel changes... and no shipping or wait time is required. If you bowl, you may even already own one...

[Hugh]

"Also picked up the ideas of using a solvent like perhaps Kroil on the threads before removal attempts. Some time in the freezer as suggested before is good too I think. The Luger receiver and barrel as you know are kinda dainty really, sometimes a sharp hammer blow on the action wrench is worth more than an average sized guy jumping on the end of a 2 foot wrench."

DITTO what Rick said.

I had one bbl that twisted until the front sight was pointing DOWN before it broke loose with a loud "crack"! Often those guns that have been reblued with the "modern" dip blue have the threads rusted in.

I have found that overnight soaking in Kroil or Liquid Wrench helps loosen bbls, also , for really stubborn ones, heating the receiver area with a propane torch & then putting in the freezer overnight will help.

[G.T.]

Thanks to all for the info shared.. I have a pretty good idea as to the necessary steps for success... but, one last question.. how far should the barrel screw on by hand, prior to wrenching it up to alignment.. I've read that the extractor width and no more is acceptible, others have told me 1/8" is enough... seems like it gets pretty tight, pretty fast! .... Best to all, til...lat'r....GT

[Hugh]

All the "new" German field armory replacement bbls I have used would hand tighten to within a extractor slot or close. New after market bbls vary, some will come close, some won't, most will require a little turning on the face of the flange to fit. As Rick says, be sure to use lots of antisize compound on the threads and flange. I have had bbls that would require tightening and loosening several times to mate the bbl to the receiver in the correct position.

[G.T.]

OK guys! Barrel removal is a snap... The rosin was just the ticket and my receiver wrench is work'en great... so, now I try to screw in an original barrel from another receiver, aaaannnndddd, it actually hits / bottoms out, on the receiver at / on, the breech face end of the barrel, leaving the flange about half a turn out...???....... Is this abnormal, un-usual, or just beginners luck!..... Best to all, til...lat'r...GT

[Ron Wood]

G.T.
A half turn out (180 degrees) seems a bit much for hard hand tightening. I would expect about a a quarter turn for hard hand tightening and about the width of the extractor groove if you are using a wrench just before the final “ugh” crank on the wrench. As you probably know already, the torque of the barrel is an “interference” or “crush” fit. Looking at the original specification drawings you can see that there is a 0.1mm taper, or dish, on the rear barrel flange that allows for a final torque for this crush fit. Naturally, the final fit may vary from one gun to the next (but in actual production, this was usually a very small and insignificant variance), so if your replacement original barrel bottoms out too soon, you may have to remove a tiny amount (I don’t do thousandths well) from the rear of the flange to get the barrel to properly index. You might have to recheck headspace, but I doubt it.
Best to you backatcha,
Ron

[sheepherder]

Originally Posted by Ron Wood

...you may have to remove a tiny amount (I don’t do thousandths well) from the rear of the flange to get the barrel to properly index...

1 turn is .050" (20tpi = .050" per thread), so your 180º = .025"...but you want to leave ~ 1/8 turn (~.003"); so you'd want to turn off ~.022"...and that should leave you an extractor width away when hand tight...

.022" will likely require you to ream the chamber a bit...

Caveat: Measure three times, cut once...

[Ron Wood]

There you go! Somebody that knows what they are talking about. I repeat, I don't do thousandths well !

[sheepherder]

Originally Posted by Ron Wood

There you go! Somebody that knows what they are talking about. I repeat, I don't do thousandths well !

"Gunsmithing" via forum posts is like diagnosing what's wrong with your car over the telephone...

There's a lot of variables at work here...Were the threads cleaned; were they lightly lubed; were there any dings; any caked crap on threads/flange faces; had it been cut down before; is it 'original' or a repro; did the 'smith' torque it down three times to 'set' the threads; is it a really tight (or loose) fit; etc...

Too many variables for any quick & easy solution...

...My $.02...Ka-Ching!!!...

[G.T.]

Hi Guys, thanks for all, I'm going to measure out a few things before I proceed... But, it's not at the flange area where the interferance is occuring.. it's at the very most back part of the barrel bottoming out in the receiver, (at the rails??) So, it would appear that the receiver is overall too short... but it doesn't apperar altered???.. Stacking thousands??, or just wrong end of the plus tolerances's??.. Annnnddd, somewhere along the line, I'm going to have to buy or make a headspace gauge... Woe is me....... but the challenge is eagerly met, ...... Thanks guys, best to you all, til...lat'r...GT

[Ron Wood]

This is probably a really stupid question, but perhaps did the barrel come from a long receiver gun?

[Hugh]

GT,
I have run into this problem a few times, sometimes it was so close that a little extra "elbow grease" tightened it on up, but left a gouge mark on the end of the bbl. On the others, it was necessary to file a little metal off the end of the bbl to give clearance. Be sure to check headspace after removing any metal from the end of the bbl. But you are doing this anyway after installing a bbl aren't you?

[G.T.]

Hi Ron, nope, all short shank outfits, and parts.. I measured from the rear toggle pin to the front of the receiver face,and compared it with another perfect condition stripped receiver, and it's to within .0015" of the other...I think all that's different is the relief clearance at the barrel base of the internal rail slots on the receiver ... ?? I can only see shaving the back of the barrel a few thou to make it fit correctly.... More mesurements to follow tomorrow... I'll know a'lot more when I'm done....Best to all, til...latr...GT....]

[G.T.]

Hi To all, and Hi Hugh! Thanks for you post..... after a few hours with the digital caliper, I found out the following... The barrel I'm using hand tightens up to exactly the same extractor width distance desired by hand on three different receivers... 1920 commercial, 1920/ model 08 commercial navy, and 1917 DWM WW1 receiver... The receiver in question, 1916 navy, measures exactly the same in all regards, within .0015" everywhere... and with the very same barrel, probably 190 to 200 degrees from straight up tight... probably 180 degrees from desired position at hand tight.. So, it apperas thet I'll have to shave the shoulder, shave the barrel breech end, and deepen the chamber / headspace... Sooooo, it apprears a finish reamer, and a "go" and "no go" gauge(s) are in the future purchases or trades list... any of you guys got any spares you're willing to let go... I've got trade bait coming and going all the time!!...... Thanks guys, this is really staring to get fun now... Now I can actually screw my own stuff up!...... Might be time to make a barrel also... we'll see.. best to all, til...lat'r....GT