Suppressors Smallest barrel diameter to thread a barrel 5/8-24.

[Prebanpaul]

I am buying a suppressor, for a 300 win mag. It is my hunting rig, talking to a very respected hide member and sponsor, it was questioned if the barrel was thick enough to thread.

I am buying it for my 260 no matter what, but just wondering if I should thread the 300 winmag.

It is a Weatherby ultra light. Barrel thickness is .62

I am really trying to thread it 5/8-24

Thanks for any information.

 

[Jig Stick]

I just posted a question about this today. It will depend on the suppressor. But from what I can tell, for a .30 suppressor with 5/8x24 threads, you need a minimum barrel OD of .750 which leaves almost all sporter barrels off limits.

 

[Prebanpaul]

thanks for the reply. I just looked at your post.

 

[ddavis]

I know it's not ideal, but my 6.5x55 Tikka barrel is threaded 1/2x28 and I use an adapter to get it up to 5/8x24 so I can screw my AAC Cyclone on. I had a 300 Whisper barrel threaded 1/2x28, and I wouldn't do it again. There is very little meat left with a 30 caliber bore. Maybe do 9/16x??? and have a 5/8x24 adapter with a shoulder permanently attached?

 

[mtrmn]

5/8 = .625 So no the barrel is not big enough to thread 5/8 x 24.
Pretty much all thread-on suppressors I know of use a flat shoulder behind the threads to snug up against. This shoulder mates up with a flat surface on the rear of the suppressor (or QD adapter) to insure proper alignment with the bore. Check out this link: http://yhm.net/pdf/762_PHANTOM_625-24.pdf
I am NOT an expert and YMMV.

 

[Zak Smith]

I just posted a question about this today. It will depend on the suppressor. But from what I can tell, for a .30 suppressor with 5/8x24 threads, you need a minimum barrel OD of .750 which leaves almost all sporter barrels off limits.

We recommend no smaller than 0.725" for 5/8-24 threads
Thunder Beast Arms Corporation [TBAC] | Tech | THREAD SPECIFICATIONS

Basically we want the thread OD to be at least 0.260" larger than the bore diameter for 24 tpi threads and the shoulder should be at least 0.100" larger than the thread major diameter.

The other poster is correct, 0.620" is too small for 5/8ths threads. It's smaller than the proper major diameter of the threads themselves, let alone any shoulder.

 

[diverdon]

I do not know what shoulder might be required for your silencer to attach and work properly, but you could put a 5/8-24 class 3A thread on your barrel. For a 5/8-24 class 3A thread [ Unified Screw Threads, Standard Series ] the Max Major Dia is .625 but the Min Major Dia is .6178. A class 2A fit would be slightly smaller.

If I wanted to do it, I would ask a qualified gunsmith if he could thread a little extra and use a lock nut for a shoulder, if your silencer needs a shoulder.

 

[RayDog]

Do not use a lock nut as a shoulder!

 

[metroplex]

Sorry to bring up an old thread, but I'm in a similar situation. I have a 300WM barrel with a OD of 0.602" at the muzzle (sporter contour). CNC Warrior shows M15x1 to be a suitable size. Any second opinions? How important is the shoulder? Because if I thread M15x1 on this 0.602" OD barrel, there probably won't be a shoulder - but the muzzle brake I intend to use (Precision Armaments Hypertap) has its own lock nut. My Tavor came from the factory with a locknut as well, and it doesn't even touch the shoulder of the barrel/muzzle.

 

[Cardinal]

I have a Wby Mkv with a 0.630" barrel which I have threaded M14x1 since its easy to find suppressor for that here. But for the US not so much.
I wouldn not go to M15X1 with that barrels of yours. Even 9/16-24 would be pushing it.

If all you want is a brake and have no plans for a suppressor, I guess a better technical solution would be M13x1 or maybe M14x1 along with another brake which you probably have to import, or get a custom made one.
Of course this is inconvenient and annoying if you every want something else on that barrel.

 

[metroplex]

Can you explain M15 or 9/16 would be pushing it? Bore is .308 and OD is 0.611 taper down to 0.602 at muzzle

 

[Cardinal]

The small shoulder. But for a brake only, it might be possible. But personally I would find other solutions.
And you have https://terminatorproducts.co.nz/ who have brakes in various threads.
Minimum diameter listed by suppressor manufacturers here for M15x1 are usually 0.650"/16,5mm

 

[metroplex]

Ah I see. I contacted Precision Arms regarding the Hypertap and said a jam nut could work as a shoulder. Tavor uses one and the SCAR17 uses one mainly for the pencil barrels. I don't think jam nuts are probably the best for a suppressor but I just need it for a brake so I'm still doing research in this.

 

[Strykervet]

You're gonna be better off using a "beveled spacer" (that's what Surefire calls it) with a QD brake I think. 9/16 is an option but it doesn't leave a whole lot ID. Steyr FAL barrels are cut like that but LH.

I'd deal with someone like TBAC or Elite Iron if I were you --someone that can give you solid advice as well as make shit happen. Listen to them. With Surefire, I still don't know what works and what doesn't because every time I call 'em I get competing answers --they just make shit up obviously. Not too goddamn reassuring on a $1500+ lifetime purchase where the warranty can be fucked if you don't do it just right. Single reason I can't recommend them for anything short of a flashlight.

 

[HansohnBrothers]

I recommend you send your rifle to TBAC and have them install a muzzle indexed brake.

 

[metroplex]

Just an update on this, I had Silencer Central cut the threads for 1/2-28 based on their recommendation and installed the Hypertap. The brake did its job, made the recoil feel like 7.62x39, not totally gone but I can go 60+ rd in a session and not feel any pain (before, the 40th round made me cringe enough to pack up that particular rifle). The first time the Hypetap loosened. I contacted PA and they recommended just tightening it more, but their small wrenches were worthless. I use two thin-jaw adjustable wrenches and made it tighter. The second session with 60+ rd didn't budge the brake at all. My next step would have been to use Rocksett.

If I had to do it all over again, I'd just get a rifle with a heavy profile already threaded in 5/8-24. I didn't realize Sporter contour meant this gun was designed to be a lightweight hunting rifle where you make 1 or 2 shots and called it a day. My mistake, but the gun is still fun to shoot!

 

[chevy_man]

The best way I've seen is what Barrett does on the fieldcraft. The contour is super light and then has a flare to about .750 so the can has a shoulder to hit.

 

[E. Bryant]

The best way I've seen is what Barrett does on the fieldcraft. The contour is super light and then has a flare to about .750 so the can has a shoulder to hit.

Agreed. Here's a similar concept as presented by Larue:

 

[elwarpo]

Thinner 30 cal barrels can be threaded to 9/16-24. Here is my FAL barrel threaded that way (RH not LH thread).

 

[Zak Smith]

#threadjobsthatmakemyeyetwitch

 

[Geno C.]

Agreed. Here's a similar concept as presented by Larue:

View attachment 7695338

I have a sporter coming from Bartlein with a flare like that. Easy enough to order

 

[brian_smith]

I am buying a suppressor, for a 300 win mag. It is my hunting rig, talking to a very respected hide member and sponsor, it was questioned if the barrel was thick enough to thread.

I am buying it for my 260 no matter what, but just wondering if I should thread the 300 winmag.

It is a Weatherby ultra light. Barrel thickness is .62

I am really trying to thread it 5/8-24

Thanks for any information.

I thread a lot of factory guns for suppressors, 9/16"-24 tpi 3a measured over wires within the tolerances in machinist handbook. I then recommend the use of a https://precisionarmament.com/m4-muzzle-thread-adapter/
I still like to have at least a .025/side "shoulder" to bump that adapter against. About .6125 barrel diameter at rear of threads, I have fudged on the small side of shoulder with no known issues, with those adapters. I also don't use an undercut to provide as much support at back of threads as possible.
People want to thread 1/2"-28 tpi on bores bigger that .224, and by how I was trained, you need at least .100" per side over groove diameter. So, in light of that .257 groove would be the maximum caliber for 1/2"-28 tpi, under the minimum thread diameter(bottom of threads). The other issue I see with threading 1/2"-28 tpi on anything bigger than .224 is someone threading a .224 muzzle device on something bigger and sheading bullets, baffle strikes or worse. That being said, anyone threading 1/2"-28 tpi on anything bigger than a .257, is setting you and them up for failure, and I would be suspect of their work.

 

[Hammer3332]

I thread a lot of factory guns for suppressors, 9/16"-24 tpi 3a measured over wires within the tolerances in machinist handbook. I then recommend the use of a https://precisionarmament.com/m4-muzzle-thread-adapter/
I still like to have at least a .025/side "shoulder" to bump that adapter against. About .6125 barrel diameter at rear of threads, I have fudged on the small side of shoulder with no known issues, with those adapters. I also don't use an undercut to provide as much support at back of threads as possible.
People want to thread 1/2"-28 tpi on bores bigger that .224, and by how I was trained, you need at least .100" per side over groove diameter. So, in light of that .257 groove would be the maximum caliber for 1/2"-28 tpi, under the minimum thread diameter(bottom of threads). The other issue I see with threading 1/2"-28 tpi on anything bigger than .224 is someone threading a .224 muzzle device on something bigger and sheading bullets, baffle strikes or worse. That being said, anyone threading 1/2"-28 tpi on anything bigger than a .257, is setting you and them up for failure, and I would be suspect of their work.

I am looking to have a tikka t3 superlight 300 win mag shortened and threaded for a suppressor. I think it will be in the 0.62-0.63 diameter range based on where I want to shorten to. I found a 9/16 to 5/8 adapter similar to what you suggest except it indexes on the muzzle. Would something like that work in lieu of ensuring there is enough of a shoulder? Aesthetically maybe not the most appealing, but I’m more of a function over form guy anyway.

 

[Hammer3332]

I am looking to have a tikka t3 superlight 300 win mag shortened and threaded for a suppressor. I think it will be in the 0.62-0.63 diameter range based on where I want to shorten to. I found a 9/16 to 5/8 adapter similar to what you suggest except it indexes on the muzzle. Would something like that work in lieu of ensuring there is enough of a shoulder? Aesthetically maybe not the most appealing, but I’m more of a function over form guy anyway.

Link: https://hughesprecision.com/product/916-24-rh-id-to-58-24-od-barrel-adapter-thread-converter/

 

[msgriff]

I am looking to have a tikka t3 superlight 300 win mag shortened and threaded for a suppressor. I think it will be in the 0.62-0.63 diameter range based on where I want to shorten to. I found a 9/16 to 5/8 adapter similar to what you suggest except it indexes on the muzzle. Would something like that work in lieu of ensuring there is enough of a shoulder? Aesthetically maybe not the most appealing, but I’m more of a function over form guy anyway.

Maybe look into having a gunsmith adding a shoulder:

 

[Hammer3332]

Maybe look into having a gunsmith adding a shoulder:

Thanks for the idea. Is that pressed on or threaded with lock tight/set screw? Once on it looks like it’s then profiled?

 

[LeftyJason]

I am looking to have a tikka t3 superlight 300 win mag shortened and threaded for a suppressor. I think it will be in the 0.62-0.63 diameter range based on where I want to shorten to. I found a 9/16 to 5/8 adapter similar to what you suggest except it indexes on the muzzle. Would something like that work in lieu of ensuring there is enough of a shoulder? Aesthetically maybe not the most appealing, but I’m more of a function over form guy anyway.

Which suppressor? I went Thunderbeast ultra 7 and had them do their face mount cb brake on my T3X lite. So the concept works. Cost wasn't bad.

 

[brian_smith]

I am looking to have a tikka t3 superlight 300 win mag shortened and threaded for a suppressor. I think it will be in the 0.62-0.63 diameter range based on where I want to shorten to. I found a 9/16 to 5/8 adapter similar to what you suggest except it indexes on the muzzle. Would something like that work in lieu of ensuring there is enough of a shoulder? Aesthetically maybe not the most appealing, but I’m more of a function over form guy anyway.

It should work great. Sorry for the long wait for reply, I don't look often.

 

[metroplex]

The KBA Custom shoulder for my Tavor got me thinking to use the Accu Washers as a shoulder. They are machined flat and sturdy enough to handle the torque from a muzzle device. However I opted to run Q's Cherry Bomb in 9mm for my 300 Win Mag threaded for 1/2-28. The Cherry Bomb for 9mm doesn't have the interior taper, so the shoulder of the muzzle device is super thick and worked perfectly with my barrel. I mainly got it as a mounting device for a suppressor.

 

[srt-4_uk]

The KBA Custom shoulder for my Tavor got me thinking to use the Accu Washers as a shoulder. They are machined flat and sturdy enough to handle the torque from a muzzle device. However I opted to run Q's Cherry Bomb in 9mm for my 300 Win Mag threaded for 1/2-28. The Cherry Bomb for 9mm doesn't have the interior taper, so the shoulder of the muzzle device is super thick and worked perfectly with my barrel. I mainly got it as a mounting device for a suppressor.

1/2x28 threads for a 300WM? Have you measured any bore swelling or seen any accuracy problems?

 

[doubloon]

thanks for the reply. I just looked at your post.

There are places out there that will thread 5/8x24 on a ~0.628 barrel without warranty. Not something I would recommend.

You could also go with a suppressor that indexes on the muzzle face instead of a barrel shoulder. I don't know what options there are for this, if any.

 

[metroplex]

1/2x28 threads for a 300WM? Have you measured any bore swelling or seen any accuracy problems?

I've had the gun for almost 3 years now with the 1/2-28 threading and logged over 600 rounds. Each time I have removed the muzzle device, the threads and bore looked fine. Accuracy/precision is about the same and hasn't gotten worse. It likes certain commercial loads, while most decent commercial loads are consistent (Norma is an example). I first started off with just using brakes (APA Little Bastard, Precision Armament Hypertap) and now Q Cherry Bomb with Q Bottle Rocket. My Omega 300 and Omega 36M Form 4's were just approved so I will be using those on this rifle, but will check the alignment rod beforehand.

I'm not sure the bore would swell... especially with a muzzle device fully threaded on. The APA and PA brakes were like 4140 steel. The Q Cherry Bomb is 17-4 SS which is still very sturdy.
I had Silencer Central thread the muzzle about 3 years ago and because of the sporter profile, I could only do 1/2-28 and they said it would be perfectly fine for 300 Win Mag.

 

[FuhQ]

Just had my smith thread a couple of old Ruger M77 MKII pencil barrels for me, and he made some custom permanently-attached 5/8-24 adapters from an old 416r stainless barrel he had laying around, that have shoulders on them. They’re not perfect, or pretty, but they’re straight, true alignment, & functional.

 

[doubloon]

Just had my smith ... custom permanently-attached 5/8-24 adapters ... They’re not perfect, or pretty, but they’re straight, true alignment, & functional.

View attachment 8177679

This would be perfect IMHO. I assume silver soldered? If your smith doesn't mind and accepts work via shipping please provide his deets just in case Ruger is able to fix my 308 Govt. rifle.

 

[FuhQ]

This would be perfect IMHO. I assume silver soldered? If your smith doesn't mind and accepts work via shipping please provide his deets just in case Ruger is able to fix my 308 Govt. rifle.

Unfortunately, he doesn’t. He’s extremely peculiar about who he does work for. He’s been doing all my work for over a decade, so I’m one of the few that can just call him and drop stuff off on a whim.

I’m not sure on the compound used, I’m guessing either some sort of permanent steel epoxy like DevCon, Permatex 4-Ton, or Loctite, or he could have used silver solder or flux?

 

[FuhQ]

This would be perfect IMHO. I assume silver soldered? If your smith doesn't mind and accepts work via shipping please provide his deets just in case Ruger is able to fix my 308 Govt. rifle.

You're in Texas I see, contact the guys over at South Texas Armament in Uvalde. And then show them the pictures I posted. I'm sure they can hook you up with something on your rifle. They do amazing work (I see their posts on instagram), and are semi-local (in-state) for you, so you might be able to drive them there, or quick-ship.

I don't have FB, but you can still see their address and phone number if you click on the link.

South Texas Armament LLC

South Texas Armament LLC. 1,343 likes · 3 talking about this. Custom Rifles and Silencer Dealer

www.facebook.com

 

[Greg Langelius *]

Do not use a lock nut as a shoulder!

OK, I read you clear; but could appreciate some form of an explanation as to why this is an imperative.

Greg

 

[doubloon]

appreciate some form of an explanation as to why this is an imperative

suppressor concentricity

When a qualified machinist threads a barrel for a suppressor the shoulder is guaranteed to provide a 'square to the bore' face for a suppressor that indexes off the shoulder, the muzzle face is guaranteed to provide a 'square to the bore face' for a suppressor that indexes off the muzzle face.

Using a lock nut to index the suppressor somewhere in the middle of the threads is not guaranteed to be square to the bore.

 

[Greg Langelius *]

Much thanks for the info. I don't do suppressors, so I am not familiar with their issues.

Greg