Gun smith for suppressor welded to a barrel

Matt98tj

Matt98tj

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I didn’t have any luck on my post in another section, so thought I’d try here. I need a suppressor welded (or permanently attached) to a barrel and need recommendations in or around the Charlotte area for a good gun smith.
I decided to weld it when I started the build so components for the build (including the suppressor I got) were purchased with permanent attachment in mind. I know this will not make BigWaylon happy, sorry man lol
 
Scsmith42 said:
Typically the process is pinned and welded. Less chance of barrel distortion compared with just welding.
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The barrel is stainless and the suppressor is titanium, so I’m not sure what the best way to weld them is? I figured I’d let a professional handle it so I don’t have to worry about messing up over 2k worth of parts lol
 
You will need a professional tig welder to do those two. I doubt you will find one, unless he is a gun guy, thats willing to do it. There is a lot of things that can go wrong in that scenario. By nature, welds distort the parent pieces and there is also a good possibility that the welds can cause alignment issues with the can.
 
Typically the threaded mount for the suppressor is drilled for a roll pin. You screw the end cap onto the threaded barrel, and then use the holes as an alignment to drill the barrel.

Instead of the hole being centered in the bore, it is offset so that the pin goes through the side of the barrel. Once the pin is driven into place, a small TIG weld is placed over the open hole to keep the pin from being removed.

This meets ATF requirements and also minimizes the chance for any barrel distortion from the welding. TIG welding is suitable for all types of metal, including Ti.

If the suppressor design does not allow a pin and weld, then rather than applying a weld bead frequently the metals can be fused together with a TIG, reducing the potential for a weld bead to distort the metal as it cools and shrinks. I don't think that this will work with Ti to stainless though.
 
Scsmith42 said:
Typically the threaded mount for the suppressor is drilled for a roll pin. You screw the end cap onto the threaded barrel, and then use the holes as an alignment to drill the barrel.

Instead of the hole being centered in the bore, it is offset so that the pin goes through the side of the barrel. Once the pin is driven into place, a small TIG weld is placed over the open hole to keep the pin from being removed.

This meets ATF requirements and also minimizes the chance for any barrel distortion from the welding. TIG welding is suitable for all types of metal, including Ti.

If the suppressor design does not allow a pin and weld, then rather than applying a weld bead frequently the metals can be fused together with a TIG, reducing the potential for a weld bead to distort the metal as it cools and shrinks. I don't think that this will work with Ti to stainless though.
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I’ve also read that brazing them might be possible? I don’t plan on doing mag dumps, so I don’t see them getting too hot. But I don’t won’t to have to worry about it coming loose either. I’m not a welder so I have no clue what the best way to attach them is?
 
you pin it with the pin going through just the edge of the barrel. Then you only do a tack weld that covers the pin. You don't actually weld the barrel to the adapter. you just weld the drilled hole shut behind the pin so the pin can't be removed....that makes it permanently attached.

That's my take on it anyway. I've always bought 16" barrels so I don't have to worry about it. I could see the need if you wanted to make a rifle with 10.5" upper and 6" suppressor combo work without an SBR stamp though.
 
papa_smurf said:
you pin it with the pin going through just the edge of the barrel. Then you only do a tack weld that covers the pin. You don't actually weld the barrel to the adapter. you just weld the drilled hole shut behind the pin so the pin can't be removed....that makes it permanently attached.

That's my take on it anyway. I've always bought 16" barrels so I don't have to worry about it. I could see the need if you wanted to make a rifle with 10.5" upper and 6" suppressor combo work without an SBR stamp though
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That’s what I’m doing. 10.5 inch barrel from dead shot, with the suppressor welded it will be right at 17 inches.
 
BigWaylon said:
He just told you. 😉

blind pin & weld if you insist in going down this road ☹️
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Whatever the smith thinks is the best way to do it and if it works is all I care about. I just know this is beyond my ability, so whatever the pro says he/she has to do I’ll listen.
Now to find someone that can make it happen?
 
Matt, typically there are three different options for attaching a suppressor so that it meets ATF requirements to be considered as part of the barrel length.

1 - Pin and weld (most desirable from the standpoint of not damaging the barrel)
2 - Direct weld,
3 - high temperature braze or silver solder.

ATF considers all of these to be "permanent". The problems with options 2 and 3 is that you have to put a lot of heat into the barrel when you're direct welding and soldering, and this in turn can cause warpage. Option 1 minimizes that potential.

Note that the suppressor mount needs to be be permanently attached to the suppressor tube (in addition to being permanently mounted to the barrel). It can only open at the discharge end of the suppressor in order to have the tube count as part of the barrel.
 
This is the project, Scar 16s in 300aac. I had MotoTech make me a custom gas regulator so i can the gas complete off. Ill be able to run it like a bolt gun (side charging handle) when hunting with subsonic ammo. Or turn the regulator one click, load a mag of super sonic and shoot semiauto. The barrel change only takes about 4min with the scar. So I can swap between 5.56 and 300aac anytime I want.
 

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Scsmith42 said:
Matt, typically there are three different options for attaching a suppressor so that it meets ATF requirements to be considered as part of the barrel length.

1 - Pin and weld (most desirable from the standpoint of not damaging the barrel)
2 - Direct weld,
3 - high temperature braze or silver solder.

ATF considers all of these to be "permanent". The problems with options 2 and 3 is that you have to put a lot of heat into the barrel when you're direct welding and soldering, and this in turn can cause warpage. Option 1 minimizes that potential.

Note that the suppressor mount needs to be be permanently attached to the suppressor tube (in addition to being permanently mounted to the barrel). It can only open at the discharge end of the suppressor in order to have the tube count as part of the barrel.
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So pin and welded would be the best if I can find someone to do it. In your opinion?
 
what suppressor and what mount?
if you're using a modular one that has the ability to separate the mount from the can, you're still making a SBR, just one with a strange muzzle device.

Look for a sealed can (generally referred to as not user serviceable). As has already been said, the part that attaches to the muzzle will either have a pilot hole drilled, or will have a flat for a wrench that can be used for a solid place to make the blind pocket for the pin to sit in. Lots of people have met all legal requirements doing it their selves with a drill press, a piece of wire hanger, and a welder.
 
DrScaryGuy said:
what suppressor and what mount?
if you're using a modular one that has the ability to separate the mount from the can, you're still making a SBR, just one with a strange muzzle device.

Look for a sealed can (generally referred to as not user serviceable). As has already been said, the part that attaches to the muzzle will either have a pilot hole drilled, or will have a flat for a wrench that can be used for a solid place to make the blind pocket for the pin to sit in. Lots of people have met all legal requirements doing it their selves with a drill press, a piece of wire hanger, and a welder.
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It’s a gemtech gmt-300. It’s direct thread, but it’s serviceable so I can clean it after subsonic rounds.46882128-6EF4-487D-8D29-C0D9810767FA.jpeg
 
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Matt98tj said:
It’s a gemtech gmt-300. It’s direct thread, but it’s serviceable so I can clean it after subsonic rounds.
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From what I know of that suppressor, it's not a good candidate for a permanent mount.

The GMT 300's that I'm familiar with are a monocore design where the tube screws over the monocore. Unfortunately the monocore itself has to be threaded directly onto the barrel.

If you pin and weld it, you have no way to remove the monocore baffle assembly for cleaning.
 
Scsmith42 said:
From what I know of that suppressor, it's not a good candidate for a permanent mount.

The GMT 300's that I'm familiar with are a monocore design where the tube screws over the monocore. Unfortunately the monocore itself has to be threaded directly onto the barrel.

If you pin and weld it, you have no way to remove the monocore baffle assembly for cleaning.
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You can knock the chunks out with a chisel or pick. It’ll be ok cleaning. 😁

The bigger issue will be figuring out a pin & weld spot. It sits flush on the shoulder. Not sure if you could remove the tube and get a pin in from the inside or not.

Something designed like the GA Spartan 3 (although it’s a 5.56 can) is much better…as it has a protrusion on the mounting end as well as a hole ready for a pin.

188FB80C-44B1-4D4C-9141-4B63B431F1BE.jpeg
 
there are definite drawbacks to sbr if you plan to move around from state to state. you can sort of bypass those if you pin/weld... but the requirement to do paperwork will catch up with you eventually.

as for subsonic 300, that's something i should be thinking about. i don't think my .30 can or the other 2 i have on order are serviceable that way. I don't fire a lot of subs though (or 300 at all anymore. everything i have is in a mag or two), so the occasional mag of supers will probably sweep things through.
 
Scsmith42 said:
From what I know of that suppressor, it's not a good candidate for a permanent mount.

The GMT 300's that I'm familiar with are a monocore design where the tube screws over the monocore. Unfortunately the monocore itself has to be threaded directly onto the barrel.

If you pin and weld it, you have no way to remove the monocore baffle assembly for cleaning.
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The monoocore is attached to the thread. It’s just the outer cover that is removable, so the overall length will still be +16 inches.
 
DrScaryGuy said:
there are definite drawbacks to sbr if you plan to move around from state to state. you can sort of bypass those if you pin/weld... but the requirement to do paperwork will catch up with you eventually.

as for subsonic 300, that's something i should be thinking about. i don't think my .30 can or the other 2 i have on order are serviceable that way. I don't fire a lot of subs though (or 300 at all anymore. everything i have is in a mag or two), so the occasional mag of supers will probably sweep things through.
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I’ll run 10-15 rounds of 308 on my other can after shooting subsonic 300. 2650fps will clean it out no problem.
 
amnesia said:
Silly question but why wouldnt you SBR it? The cost the pin and weld should be about the same?
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I hate paying the government to have my rights sold back to me is the main reason. I don’t have a choice with the suppressor. But If there is a workaround, weld the suppressor to the barrel, or buy a multical upper. I’d rather pay my hard earned money to someone who is trying to earn my $, not just demand it 😊
 
My check was cashed in of January so I’m hoping to have my suppressor in the next 3 months. Like I said I bought everything with permanent attachment in mind. But if there is a better way, I’d be interested.
1: permanently attach suppressor to barrel $150-$250 (just guessing)

2: buy a upper receiver and pistol brace. $650 f&n stuff is expensive.

3: sbr it. If I was going to do this I probably would have got a true 30cal suppressor, but I was trying to keep everything light and short (10.5 is as short as I could go on the barrel with the gas system) and I hate paying $200 again for paper work.

Anyway that’s my situation lol
 
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SBR it. Yes, it's $200, but if you form 1 it, you'll have it long since ready and waiting when you finally get the suppressor stamp.
nothing wrong with a 2stamp rifle
 
On a positive note…I really like the design of the GMT-300BLK. So much so I have a Form 1 version for my AR57. It’s similar in the two piece design, but not the baffles. The upper on the AR57 has a integral rail, so this way there’s no chance of leaving a piece behind. It also has the square opening on the end so I can use a ratchet wrench (w/o a socket attached).

As I mentioned earlier, the lack of a good P&W spot is gonna be the issue.
 
In case it wasn’t clear above, you’ll want the pin to be installed at a tangent to the bore and it doesn’t need to cut into the barrel more than the depth of the threads that are already cut in the barrel.

The ATF probably wouldn’t approve it in advance, but you could drill it, thread that hole, locktite in a long screw to lock it all together, file off the screw and ceracote the thing. Can’t do it with a hand drill, but could with a drill press.
 
BigWaylon said:
On a positive note…I really like the design of the GMT-300BLK. So much so I have a Form 1 version for my AR57. It’s similar in the two piece design, but not the baffles. The upper on the AR57 has a integral rail, so this way there’s no chance of leaving a piece behind. It also has the square opening on the end so I can use a ratchet wrench (w/o a socket attached).

As I mentioned earlier, the lack of a good P&W spot is gonna be the issue.
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Yeah I was thinking just welding it because of the lack of space for a pin.
But I’m starting to think this is going to turn into a pistol or sbr. I’ve call 3 places now and none of the smiths will do the work. So without someone to do it I’m down to option #2 or #3.
 
I doubt you will find anybody to weld it. Nobody is going to want to guarantee/warranty the weld work.
I Tig weld every week and would be mucho hesitant to take this job.

Can you weld SS and Ti?
Yes...

Will a SS/Ti weld crack?
Yes.... sooner or later the Ti will crack.

Get @BigWaylon to help you with the SBR procedure and never worry about it again.
 
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BigWaylon said:
On a positive note…I really like the design of the GMT-300BLK. So much so I have a Form 1 version for my AR57. It’s similar in the two piece design, but not the baffles. The upper on the AR57 has a integral rail, so this way there’s no chance of leaving a piece behind. It also has the square opening on the end so I can use a ratchet wrench (w/o a socket attached).

As I mentioned earlier, the lack of a good P&W spot is gonna be the issue.
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Looking at pictures of it online it has a knereld end that looks like it could be used or the smith doing the work could pin and weld it in the threads for the outer and recut them into the weld/pin.
 
Mike79 said:
Looking at pictures of it online it has a knereld end that looks like it could be used or the smith doing the work could pin and weld it in the threads for the outer and recut them into the weld/pin.
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My issue is no one even wants to look at it, to see if they can. I figured any gun smith could do it. But apparently that’s not the case.
 
Matt98tj said:
My issue is no one even wants to look at it, to see if they can. I figured any gun smith could do it. But apparently that’s not the case.
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Call a machine shop just have all the info. They can drill ti use a ti pin (might have to make it) and tig it up.
 
Mike79 said:
Possibly some legal hurtles.....can a machine shop do it same day if the owner of the suppressor is present?
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No.

Working on NFA controlled items without proper credentials is a no-no.
That is probably(?) why the "gunsmiths" turned the job down.
Most "gunsmiths" are not skilled Tig welders either.

If caught, A shop owner would risk hefty fines for handling NFA items without credentials. Alot of bad press could be generated against the shop as well.

A shop that does Ti work AND is properly equipped and credentialed to do the work is probably going to charge more than either option 2 or 3 posted above.
 
Hashknife said:
No.

Working on NFA controlled items without proper credentials is a no-no.
That is probably(?) why the "gunsmiths" turned the job down.
Most "gunsmiths" are not skilled Tig welders either.

If caught, A shop owner would risk hefty fines for handling NFA items without credentials. Alot of bad press could be generated against the shop as well.

A shop that does Ti work AND is properly equipped and credentialed to do the work is probably going to charge more than either option 2 or 3 posted above.
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To clarify…

There’s nothing special about working on NFA firearms. You need specific credentials to manufacturer and/or sell…but any gunsmith can take possession of an NFA item for things like a pin & weld. They just can’t make new parts that would be considered NFA items (like baffles).

Now, I do think the ATF changed their opinion of “being in the business” in the last several years which would require an FFL…even if the person having the work done was present.
 
Hashknife said:
No.

Working on NFA controlled items without proper credentials is a no-no.
That is probably(?) why the "gunsmiths" turned the job down.
Most "gunsmiths" are not skilled Tig welders either.

If caught, A shop owner would risk hefty fines for handling NFA items without credentials. Alot of bad press could be generated against the shop as well.

A shop that does Ti work AND is properly equipped and credentialed to do the work is probably going to charge more than either option 2 or 3 posted above.
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I’ve got my doubts about the correctness of this. It’s really no different than handing my SBR with a suppressor to a buddy to shoot while I stand there. So long as the shop isn’t making either an sbr or a suppressor and you’re there in possession, then all should be good.
 
JimB said:
I’ve got my doubts about the correctness of this. It’s really no different than handing my SBR with a suppressor to a buddy to shoot while I stand there. So long as the shop isn’t making either an sbr or a suppressor and you’re there in possession, then all should be good.
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It not even close to the same thing.

Call the ATF and ask. Please post their answer here.
 
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