Suppressor Barrel Threading - Should Gunsmith know to leave a shoulder?

Joined
Apr 7, 2022
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I have a 5/8 direct thread suppressor. I also have Savage Axis .30-06 (21" sporter barrel) that's a tack driver. I took the rifle to a gunsmith to have the barrel cut to 18" and threaded for my suppressor. He asked what size threads, i told him 5/8 would be nice to avoid running an adapter on for my suppressor. He cut the barrel to 18" and threaded in 5/8" but there is almost zero shoulder now, maybe .025". I have obviously done a ton of research now on recommended measurements and shoulder requirements, but shouldn't a gunsmith have known a suppressor requires .100" minimum shoulder and recommended he thread in 9/16" or 1/2"? I won't shoot my gun with suppressor threaded on in this condition and i'm rather aggravated to say the least. Thoughts?
 

Outhunting

Lil-Rokslider
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Feb 25, 2014
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I dropped off 5 rifles to have threaded with a gunsmith that has done a lot of other things for me. He also has multiple cans on his rifles and I assumed he knew what he was doing. He threaded every one of them to long and when I got home and noticed that all of them were cut wrong and called him about it he told me to just get an adapter. He didn't go by spec at all and just pulled his own specs out of his ass.
I found another gunsmith that was highly recommended and he cut off all the threads, cut them to spec and recrowned the barrel. I lost some barrel length but they are done right now. Lesson learned for me. Bummer for you to go through that, been there!
 

BBob

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Thoughts?

This can be fixed. The 5/8 thread would have to be carried back a bit further and a threaded disk/cylinder added. It gets finished to dimension and now acts as the shoulder. There’s a bit more detail to it to get it to look nice but that’s basically it. These were done by Shaen Rifles. Don’t think he’s taking any new work though. There’s a tikka thread showing several of these. Ultimate Reloader does one in a video. I believe Karl Feldcamp will do it as well. It’s not that hard to do you just have to find someone to do it.
IMG_0676.jpeg

 
OP
B
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Apr 7, 2022
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Great info there! Thanks for the options. I was curious if the 5/8” threads could be machined off and 1/2” threaded ‘in their place’ without removing any more length from the barrel. But I solutions presented above.
 
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It’s probably not that he didn’t leave a shoulder, and more that where the threads were cut, the barrel didn’t have a large enough diameter to provide the needed shoulder. I’m a proponent of the Sig/Q 25* taper, it allows a great shoulder on a much thinner barrel, even with a device that needs a 90* shoulder, you just use a simple washer like the one posted above but it’s cheap.
 
OP
B
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Yes, I know that he didn't forget to machine a shoulder. I was implying that he should have measured the barrel O.D. at 18", subtracted the max diameter of 5/8" threads, and realized... oh this will not leave a sufficient shoulder to mount a suppressor. I better recommend to the gun owner that he use 9/16 or 1/2
 

ORJoe

Lil-Rokslider
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Customer wanted 5/8 thread and customer is always right.
If he recommended a 1/2" thread the story could have easily been "My gunsmith is an idiot who thinks you can do 1/2" on a 30 cal avoid this guy."
He might know it's fine, but he doesn't know that you know it's fine.
Adapting a 9/16 barrel thread to 5/8 can thread would be a little hairy.

Anyways, put the can on. If it lines up it lines up, shoot it.
[Edit: I thought 0.025" radius. If it's .025 diameter/.012" radius, probably a good call to not use it.]
If you don't like it, rethread to 1/2" and buy an adapter. The adapter will be seem cheap after you pay the man twice to thread your rifle the way you asked him to twice.
 
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OP
B
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Sounds like he did just what you told him to do. If you know all that shoulder stuff, you also know what the barrel measures where you wanted it threaded and if it would even work.
I do now. I only started looking at things in depth when I realized the suppressor didn’t shoulder up firmly. I guess i was looking for a little more professional expertise/guidance from the gunsmith.
 
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Mine cut my tikka 5/8 at 16” when it was .670. He then machined a little washer that my supressor brake shoulders up against that also butts up to the barrel shoulder. Essentially a step I guess . Red loctited it in place and I haven’t had issues. With a 19 ounce can
 

fwafwow

WKR
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I think he should but it never hurts to give the exact specs from the suppressor manufacturer. But I did that with Cooper and they still managed to eff up one of my rifles (even though they did the other one correctly).
 

Woogs402

FNG
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Aug 24, 2023
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I've been doing a little research about threading recently because I want to suppress my .270 Winchester Model 70 for hunting but don't want it f-ed up. What should I expect to pay for a good gunsmith to do it? Any recommendations out there? I'm in TX but would ship.
 

khuber84

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Did you specify a length you wanted barrels finished at? Did you say, oh thread em I think 5/8x24? Did you specify class? I mean gunsmiths shouldn't be left up to make their own decisions with your guns. You direct them to absolutely what you want, thread size at what length, thread class, there should be a small releif between rear most thread and shoulder as well. If gunsmith finds something that's not right with your desired plan, at that time job stops, he gets with you and a plan of the CUSTOMERS satisfaction of desired outcome within specific machining standards is adhered to.

There are a lot of shade tree gunsmiths out there. A guy who's reputation was good, cut me a barrel, and the base of chamber is WAY oversized, fired brass is coming out 4735 fired, should be about 4705. My reamer is 4714. His fixture is wobbly, using a floating reamer holder, and prob wasn't dialed in under 001 all results in a fat oblong chamber. Don't trust your money to anyone but the ones who know how to do it right.

There are a few right ways, too many wrong ways to do this stuff. That barrel is junk now, can't rechamber as the tenon is too short, gunsmith won't do anything about it, I'm out 1100$, and can't consciously sell it off. If you find a good gunsmith, befriend him, make him happy, keep him busy, spread word of his abilities, and plan ahead to keep component wait times down.
 
OP
B
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I've been doing a little research about threading recently because I want to suppress my .270 Winchester Model 70 for hunting but don't want it f-ed up. What should I expect to pay for a good gunsmith to do it? Any recommendations out there? I'm in TX but would ship
Around $100 in central PA
 
Joined
Jan 27, 2022
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I've been doing a little research about threading recently because I want to suppress my .270 Winchester Model 70 for hunting but don't want it f-ed up. What should I expect to pay for a good gunsmith to do it? Any recommendations out there? I'm in TX but would ship.

If you just want it threaded, then $75-$100 is the going rate and you should be able to find a smith near you to do it. There are a bunch of good ones in TX.

If you want it threaded with the collar, as shown above then it is $125-$150. There may be a smith in TX that is doing this now, but all the ones I know are in the mountain states so add in the shipping both ways.
 

Veloci_Wrench

Lil-Rokslider
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Apr 16, 2022
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It’s probably not that he didn’t leave a shoulder, and more that where the threads were cut, the barrel didn’t have a large enough diameter to provide the needed shoulder. I’m a proponent of the Sig/Q 25* taper, it allows a great shoulder on a much thinner barrel, even with a device that needs a 90* shoulder, you just use a simple washer like the one posted above but it’s cheap.
+1 on the Sig/Q Taper. It's pretty ingenious as it requires much less barrel diameter to achieve repeatable & concentric suppressor lock-up. Also, should require less machine time than your smith machining and securing a step behind your threads.

Most modern cans are being threaded to HUB specs (1.375x24) nowadays, and you can find HUB adapters in 1/2x28 or the 5/8x24 Sig taper if you prefer the larger threads for a 30 cal bore.
 

thinhorn_AK

"DADDY"
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I suggest you see if the company that made you suppressor can do it.
Thunderbeast has a schematic diagram on their website you can print off to show a gunsmith too, or they can do it for you. I’ve seen enough crappy thread jobs that I’d pay the extra a ship to a reputable place. Shaen rifles, TBAC, kampfield, LRI is pretty much my list. No way I’d be having a “local” guy do that for me. If it’s not done perfectly you’ll ruin your silencer and maybe hurt yourself or somebody else.
 

fwafwow

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Thunderbeast has a schematic diagram on their website you can print off to show a gunsmith too, or they can do it for you. I’ve seen enough crappy thread jobs that I’d pay the extra a ship to a reputable place. Shaen rifles, TBAC, kampfield, LRI is pretty much my list. No way I’d be having a “local” guy do that for me. If it’s not done perfectly you’ll ruin your silencer and maybe hurt yourself or somebody else.
Yep. I sent a diagram once to Cooper. They followed it once, but not the second time. TBAC had to fix it, and that’s why I’ve sent my most recent new rifle to cut the barrel and thread it.
 

thinhorn_AK

"DADDY"
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Yep. I sent a diagram once to Cooper. They followed it once, but not the second time. TBAC had to fix it, and that’s why I’ve sent my most recent new rifle to cut the barrel and thread it.
That sucks. If Shaen rifles starts taking orders again, I’d get on his list. He did mine and they are perfect.
 
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