Gunsmithing Barrel thread and shoulder machining?

SB545

Sergeant of the Hide
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Nov 3, 2019
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I may have messed up. Went with a new to me smith and am a little concerned about the work quality. 2 of the three rifles have some issues. one has jagged threads that might clean up with a chase but it has me worried about the runout while it was in the jig. the other has a bit of a bumpy shoulder with some tool marks. should i be taking these to another smith to check out?
 
This will be for a suppressor.
 

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Wow, that’s just garbage.

Edit: Regarding the boogered thread, looks like a few passes we’re made out of time with the rest of the thread, which created two flanks where there should be one. With all the gnarly burrs, I would not torque anything on to that, as it may become stuck.


Get your money back.
 
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I just got sick.... ugly machining....
What did they say when you asked them.

he said he could chase the one but liked how tight it locked up as it is. i haven't bothered to ask about the shoulder of the other. unfortunately, i was distracted by my other issue on the 3rd gun. threads looked nice but the safety doesn't function and the trigger pull varies. it was a new out of the box rifle from cabelas and the photo i saw of the throat erosion plus worn internal parts lead the smith to believe otherwise.
 
he said he could chase the one but liked how tight it locked up as it is. i haven't bothered to ask about the shoulder of the other. unfortunately, i was distracted by my other issue on the 3rd gun. threads looked nice but the safety doesn't function and the trigger pull varies. it was a new out of the box rifle from cabelas and the photo i saw of the throat erosion plus worn internal parts lead the smith to believe otherwise.
Then it should have gone straight back to them before he "smithed" anything.

Reach out to some of the reputable Smith's on this site and you will be amazed.
 
i'm a bit leery now. of the two smiths i used before, one retired and one passed away. both did good work. not sure who to trust. this guy has good reviews online. sounds like he threads a bunch of rifles. i even left them with him for a month. all i asked was that he take his time and do good work...since this was for my first suppressor. didn't want any baffle strikes right out of the gate. maybe i am better off with a factory threaded rifle. i just didn't trust the mass produced stuff.
 
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the one pictured with the jagged threads would shoot sub 1/2 moa on its worst day out 1000. it often would keep 10 shots sub 1/3 moa. i hope that stays the same. factory rifle to boot.
 
i'm a bit leery now. of the two smiths i used before, one retired and one passed away. both did good work. not sure who to trust. this guy has good reviews online. sounds like he threads a bunch of rifles. i even left them with him for a month. all i asked was that he take his time and do good work...since this was for my first suppressor. didn't want any baffle strikes right out of the gate. maybe i am better off with a factory threaded rifle. i just didn't trust the mass produced stuff.


You’re not better off with factory threaded rifles. Send those to any number of smith’s on this site, they’ll chop off those stumps and give you high quality bore concentric threads.
 
i really hope the other rifle is ok. I asked for 17" of barrel but told him to take it back to where he could safely thread 1/2-28. it ended up at 16" so there's nothing left to chop without going thru the BATF.
 
Without getting too far into it. I’m 99% positive he didn’t even measure the theads on the rough looking one. I would say he just did the guess and try it out method.
 
Jeez...
I'm trying to figger out how to get that kind of chatter on the face of the shoulder. I don't think I could do it if I tried.

Looks like there may be enough meat on the tenon to turn down and re-thread with smaller diameter, and use corresponding adapter for the can?
 
Looks like he didn’t have the barrels good and secured in the machine meaning he had it only supported in the chuck and let it dance on him for the chatter but he is no machinist for sure. No pride in his work
 
Jeez...
I'm trying to figger out how to get that kind of chatter on the face of the shoulder. I don't think I could do it if I tried.

Looks like there may be enough meat on the tenon to turn down and re-thread with smaller diameter, and use corresponding adapter for the can?
I was thinking the same thing. He must have been turning without a live center to have that kind of chatter, but it looks more like the marks are pressed in. Either way, I would NOT put anything on there. I think you should take them to a smith and get his opinion.
 
One way to save the 16" barrel would be if your suppressor attaches to a muzzle device like a brake or flash hider. You could have someone cut and rethread then permanently attach a muzzle device to bring it back longer than 16".

Another option is to have a Smith who knows what he is doing dial it in on the lathe, pick up the thread, take a clean up pass on the threads and shoulder, and then measure to see if it is in spec. It might be possible to take a clean up cut and still be left with an in spec thread.
 
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I may have messed up. Went with a new to me smith and am a little concerned about the work quality. 2 of the three rifles have some issues. one has jagged threads that might clean up with a chase but it has me worried about the runout while it was in the jig. the other has a bit of a bumpy shoulder with some tool marks. should i be taking these to another smith to check out?

Who ever machined those barrels doesn't understand how to set up their tooling or care about the end result. The barrel shoulder has chatter but can be saved, the threading tool was rubbing and those threads may be a wash. If I had that barrel in my lathe I'd cut it off and start over. Any competent smith/builder will do the same.
 
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One way to save the 16" barrel would be if your suppressor attaches to a muzzle device like a brake or flash hider. You could have someone cut and rethread then permanently attach a muzzle device to bring it back longer than 16".

Another option is to have a Smith who knows what he is doing dial it in on the lathe, pick up the thread, take a clean up pass on the threads and shoulder, and then measure to see if it is in spec. It might be possible to take a clean up cut and still be left with an in spec thread.


If the existing thread is anything close to the appropriate pitch diameter then this option won't work.
 
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In/out in a few days. The "short one" as you stated will require a new barrel as there's nothing left to pull off the front of it.

Bummer, we can help though and are happy to do so.

C.
Has anyone ever tried an tested a barrel that has been spray welded at the end, to correct anything like this?



I have had large shafts for machinery spray welded and re machined.
The metallurgy most likely couldnt be matched easily and cost would be too high from my experience.
 
Too late for my comment and sorry your barrel is toast. Just my uneducated opinion but never, ever have a barrel cut to exactly 16”. 16.5-16.75”. Should there ever be a screw up, accidentally drop it with no thread protector, gunsmith screw-up, friend cross threads your suppressor on. Whatever, there is still enough meat to thread again and not have to buy a new barrel. 1/2-3/4” is not going to make any difference in the long run. Except maybe save you from buying a new barrel.
If it was LRI or one of the other very top tier smiths, I would think about 16.000”. But accidents can still happen after you get it back.
 
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Just to clarify:

the one with really bad threads is cut 5/8-24 and is a savage 12 LRP in 6.5 CM. the one with a horrible shoulder is a savage 223 w/ a target bbl threaded 5/8-24 as well. not sure if threads can be salvaged there either. they look better but still doesn't thread anything on with out some effort. the 3rd rifle is a kimber hunter pro threaded 1/2-28. it was supposed to be 17" inches. i wanted 18" but we agreed there would be more meat to thread with a good shoulder at 17". not sure how it ended up at 16" but i haven't had time to measure it since the smith still has it in his possession. he found it had a bad chamber and inoperable safety.

here's the email to the mfg stating the issues:

He brought it to me to thread the barrel for a suppressor he is purchasing.
When I completed the threading job I was reassembling the rifle and noticed the safety does not function. I tried to make adjustments where I could but could not get it to work. It looks to me like its going to need a firing pin stop to hold back the firing pin with the safety. I also test fired the rifle in my testing and found that the case stuck in the chamber and would not release until completely cooled. I suspected a rough chamber was the cause, and confirmed that with a bore scope. I have enclosed pics of the rifle. I dont believe this was a new rifle when he purchased it.
I was surprised when he told me it was new in the box when he brought it to me.
The bolt, Locking lugs and Firing pin all showed wear. There is also a mark in the front of the stock.Also the Firing pin screw had been turned and marred before I worked on it. The rifle was also dirty inside from being shot so I assumed it was a used rifle.

so, with the smith still involved in the situation, i'm kind of in a pickle for now. trying to weigh my options but limited on funds. easiest option is to slap on a thread protector and forget about shooting those suppressed.
 
Well, waiting to hear from Kimber but I'm pulling the two that I have down to barreled actions and going to box them up and get ready to send them off. Time to start saving my Amazon bubble wrap.

Thanks for the help. I'll update when I get them back.
 
The 5/8"-24 threads can be easily turned off and fully cleaned up for a 9/16" tenon of whatever common pitch is desired.
9/16" still leaves adequate barrel wall thickness for a 6.5- unless you must have the 5/8" tenon there's no reason to cut the barrel.
5/8" minor is .575, well above the .562 and under needed.
 
Well, waiting to hear from Kimber but I'm pulling the two that I have down to barreled actions and going to box them up and get ready to send them off. Time to start saving my Amazon bubble wrap.

Thanks for the help. I'll update when I get them back.

In my current situation I realize that I never updated the thread. I sent the barrels off to morgan at class III machining and they came back looking great. He had to start over with the worst one but saved the others. Now to my reason for revisiting this thread. I was looking for these pics to compare the new barrel I had built. For whatever reason I just have bad luck with getting clean threads the first try. I'm returning this barrel due to a separate reason but the treads alone would be enough for me to send it back. Fwiw, this was after I tried to chase the threads with an adapter. They look better here than when I took it out of the box.
 

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I’m not sure what they did to make such bad threads but I’d be ashamed of that personally and surprise they let it leave the shop.
Almost looks like they had the tooling low and work was trying to crawl over the tool or it was carbide and going to slow and easy.

I’m new at cutting barrels and my stuff is WAY better!
 
Who was the original smith who did your barrels?

You could save other's here on the forum the same grief you experienced by ousting the offender. I wouldn't want any others to spend their hard earned cash there, or waste their precious time if that happened to me. And yes, time is money!

A good reputation is not solely based on producing a great product the first time around, but also what one does to rectify a situation if a problem should arise.

Sorry for your grief, you could prevent more!

TM6
 
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Who was the original smith who did your barrels?

You could save other's here on the forum the same grief you experienced by ousting the offender. I wouldn't want any others to spend their hard earned cash there, or waste their precious time if that happened to me. And yes, time is money!

A good reputation is not solely based on producing a great product the first time around, but also what one does to rectify a situation if a problem should arise.

Sorry for your grief, you could prevent more!

TM6

The first smith was a local out of Sandy, Utah. The guy that fixed his work was awesome. He's out of Texas and has great prices with fast turnaround. He does referral work for silencerco. The current issue is a known barrel maker. I talked to the owner today and he's going to make things right and even throw in some extras for free. After expressing my concerns I feel like his machinist will do it right. With so many positive reviews on here I'm chalking it up to my curse of bad thread jobs.
 
I've seen newbies make cuts with a dull tool and no coolant and they still looked better than your first pics.
Somebody up above suggested he used a loose chuck and I don't think that would even do it.
 
Hey, it's me again. Sorry I keep coming here with the same issue but apparently I learn the hard way. I got the new barrel back with the correct chambering but it appears the threads are still a bit rough. What is the best way to smooth these out? It seems like the rough major does not contact the minor on my suppressor adapter, which is good.

Is there a safe way to smooth these out without damaging the threads or loosening the lockup between the suppressor and the barrel?
 

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Who did that last one? No good way to fix them without a lathe, and a band saw.

It's a custom barrel from a known mfg out west. I'll give him a chance to make it right but I really need my action back. He offered to cerakote it with the barrel but it didn't come back. I'm hoping they didn't lose it.

I make good decisions elsewhere in life, I promise.
 
So wait is that last pic after he made things right? And he lost your action??? Was one of the extras he threw in a jar of Vaseline?