I have a suppressor that is threaded 9/16-24 and I want to have it threaded 5/8-24 to fit more platforms. Is this possible to do with what little material there is available?
Gunsmithing Changing the threads on a suppressor
- Thread starter Shooter McGavin
- Start date
Nope. Only 1/16" difference between the two.
But there may be some places that can modify it. It just won't be as easy as reaming and re-tapping.
But there may be some places that can modify it. It just won't be as easy as reaming and re-tapping.
You could get an adapter, TROSUSA does custom work, but I'd probably just have the barrel cut a little shorter with the new thread.
Any adapter would have to screw on over your barrel, extend forward with some free bore and then have the other thread. I think it would look bad and be hard to clean.
Any adapter would have to screw on over your barrel, extend forward with some free bore and then have the other thread. I think it would look bad and be hard to clean.
Depending on what you have, ECCO Machine and Fabrication, seems to have a good reputation for suppressor mods, but as others say, it’s not as simple as re-threading. If you really want to move forward on this I would give them a call. Good luck.
It can be done.
Assuming there is a way to dial the suppressor in with the bore of the baffles running concentric to the lathe spindle:
-Bore the existing threads to within the minor diameter tolerance of 5/8-24 3B threads.
-Pick up on the old thread root with an internal single point threading tool and thread like normal until a go/no-go 5/8-24 3B gauge passes.
The difficult part of this is dialing the suppressor in on the lathe. Many suppressors will be constructed where the outside of the tube does not run concentric or straight to the bore so you can't simply shove it in a 4-jaw chuck and go.
Assuming there is a way to dial the suppressor in with the bore of the baffles running concentric to the lathe spindle:
-Bore the existing threads to within the minor diameter tolerance of 5/8-24 3B threads.
-Pick up on the old thread root with an internal single point threading tool and thread like normal until a go/no-go 5/8-24 3B gauge passes.
The difficult part of this is dialing the suppressor in on the lathe. Many suppressors will be constructed where the outside of the tube does not run concentric or straight to the bore so you can't simply shove it in a 4-jaw chuck and go.
I have done the adapter in the past and was hoping it might be possible to change the threads instead. I am sure someone could cut and weld a new end onto it than recut the threads. I was just wondering if it could be done without doing all of that. That seems like a no. I might go a different route as I was looking for a suppressor for a lever action in .357 and I could have this .30 can opened up to shoot the .357. Than have the lever action threaded 9/16-24 and then dedicate that can to the rifle.
Re-boring a suppressor to accommodate a caliber larger than originally manufactured for requires a new stamp, according to the ATF handbook. Just keep that in mind.
But picking up a 9/16-24 thread and opening it to 5/8-24 is not a terribly difficult operation assuming, as others have said, that you get the threads running true before machining.
"If alterations to a silencer would increase the overall length or change the diameter or caliber of a
silencer, this is the making of a new silencer, as opposed to a repair. The new silencer must be registered and transferred in accordance with the NFA and the GCA. Alterations to a registered silencer
that result in a minimal reduction in the overall length for purposes of rethreading are permissible as 178 repairs."
But picking up a 9/16-24 thread and opening it to 5/8-24 is not a terribly difficult operation assuming, as others have said, that you get the threads running true before machining.
"If alterations to a silencer would increase the overall length or change the diameter or caliber of a
silencer, this is the making of a new silencer, as opposed to a repair. The new silencer must be registered and transferred in accordance with the NFA and the GCA. Alterations to a registered silencer
that result in a minimal reduction in the overall length for purposes of rethreading are permissible as 178 repairs."
Good to know. I guess I am in the market for a new suppressor and the thread doesn't matter anymore.
If changing the thread diameter counts as making a new silencer then how can Ecco machine change out 51t mounts to other styles?
Edited to correct my stupid not remembering exactly what the first post said.
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It's actually not irrelevant at all. His last post stated:
" I might go a different route as I was looking for a suppressor for a lever action in .357 and I could have this .30 can opened up to shoot the .357."
I was simply letting him know of the ATF's opinion on "opening up" the can to accept .357 diameter bullets.
Re-threading the can has nothing to do with that, of course.
OP said he wanted to get a .30 bore can opened up to allow .357 in addition to the mounting thread change.
Edited the post. Didn't remember exactly what the first post said.
I have been thinking about it and I believe I will do a form 1 and then change the .30 can to a 9mm for the lever action. Should make it really quiet. It will cost me $200, but that’s cheaper than buying a new suppressor and tax stamp.
yes this could be done very easily, depending on the can they would just machine and weld in a plug and machine that or cut the back off and just weld in a new section and machine that. Ecco machine is who you want to talk to.
I'll keep them in mind. To be honest I have been looking at a DeadAir can for 9mm for the lever action as I can use it on other 9mm carbines I have and it would be lighter than the .30 can I have.
Well, I just purchased the Dead Air Wolfman 9mm. So, the old suppressor will stay .30 and I'll just use an adapter to fit on other .30 rifles. Now to wait. In the mean time I am going to put a M-Lok rail on the lever gun with a red dot. Should be fun to shoot when the suppressor gets out of jail.
Turn a cylinder with 9/16-24 male threads on it, and a proper shoulder-- all in 1 op. Part it off. Screw said cylinder into suppressor, use the cylinder section to dial it in.
Bore it to proper ID for 5/8-24 female threads, ID thread to 5/8-24.
Easy. I'd do it anyway if it's 9/16-24 right now. Will be able to put it on more guns in the future.
Bore it to proper ID for 5/8-24 female threads, ID thread to 5/8-24.
Easy. I'd do it anyway if it's 9/16-24 right now. Will be able to put it on more guns in the future.
How would you hold the suppressor to dial it in?
I'd try just clamping it in a 4 jaw on the OD, but it may not work out so that the bore is concentric to the OD. Might end up never getting 2 points on the cylinder to run true at the same time. It also might work like a champ.
Either an 8-screw action fixture or a 4 jaw on the OD is probably good enough.
I've tossed cans on freshly threaded barrels before, still in the lathe. You often get .010-.020" runout on the muzzle of the can. So they're not perfect, but the bores are oversized .055-.085 or more, too.
I've tossed cans on freshly threaded barrels before, still in the lathe. You often get .010-.020" runout on the muzzle of the can. So they're not perfect, but the bores are oversized .055-.085 or more, too.
So, I did ordered a suppressor and had my lever action threaded for it. I am leaving the .30 can alone as the original plan was to bore it out to shoot .357 in the lever action and change the threads. Since boring it out would mean I have to get a new Tax Stamp for it and it might not be concentric to the bore after being rethreaded to a different pitch it just made more sense to get a new suppressor, because you can never have to many.
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