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

Prebanpaul

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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

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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.
 

ddavis

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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

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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

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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

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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.
 
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metroplex

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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

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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

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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

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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

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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

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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.