I’m having a couple of rifles built as we speak and I’m wanting to put muzzle brakes on them. I’m looking at the area 419 hellfire match brake. My question is my barrel is a benchmark contour #6 and is .750 at muzzle, so when I look at the brakes they have 1/2x28 and 5/8x24 threading. Caliber is 284 winchester, so does it matter which threading I go with or not? Thanks. Complete newbie to brakes so be easy on me if this seems like a stupid question.
- Thread starter tilman2141
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Get the 5/8x24
1/2x28 is for 223s but you can still do a 223 with 5/8x24 as well which leaves more meat under the threads which will help with any relief distortion.
1/2x28 is for 223s but you can still do a 223 with 5/8x24 as well which leaves more meat under the threads which will help with any relief distortion.
- Nov 3, 2010
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Like Rooster said, definitely go 5/8x24 on everything you can, if there's enough meat on the barrel to build a proper shoulder. And, I would even run 5/8x24 on any future bolt-action centerfire .22 caliber rifle builds, like a .223, .22-250, .22 Nosler, .224 Valkyrie, etc... But, if you can't, it won't hurt to go 1/2x28 on a 7mm as long as you plan on putting a steel muzzle brake on it, to support the threaded portion of the barrel, as 1/2x28 will leave the walls a bit thin on a 7mm bore...Just my opinion. There are some folks who have threaded some military .30 caliber barrel at 1/2x28, but I wouldn't recommend it.
Worst case scenario, you could always thread it 1/2x28, and then install a 1/2x28 (F) to 5/8x24 (M) thread adapter on it with some Rocksett... And let it cure fully for 24 hours minimum, and it will be rock-solid as if it was an original part of the barrel. It's not ideal, but it would work fine. Just make sure you get a high-quality adapter and then check your suppressor bore alignment after installation with an alignment rod before pulling the trigger one it.
Worst case scenario, you could always thread it 1/2x28, and then install a 1/2x28 (F) to 5/8x24 (M) thread adapter on it with some Rocksett... And let it cure fully for 24 hours minimum, and it will be rock-solid as if it was an original part of the barrel. It's not ideal, but it would work fine. Just make sure you get a high-quality adapter and then check your suppressor bore alignment after installation with an alignment rod before pulling the trigger one it.
Well I went with the Gen one micro bastard and it had the choice of 1/2x28 or 9/16x32 so I went with the later 9/16x32. Hope this was the correct choice on it.
I wouldn't have... But that's because you will play hell finding a suppressor mount in 9/16x32 in the future, if you ever decide to run it suppressed...Or even change muzzle brakes to something else. That's a weird archaic thread pitch that virtually nobody uses on rifles anymore. People originally started using it on 6.5 Grendel barrels, and then even all the 6.5 Grendel barrel manufacturers started slowly switching over to 5/8x24 as the standard. And now, unless a rifle is chambered in .223/5.56, the standard is 5/8x24 threads for every other cartridge for the last number of years.
The lack of a 5/8x24 offering on the brake would have been a deal breaker/hard stop for me.
Send it back and get what everyone is telling you. That is, a 5/8x24.
There's a few considerations to this:
- Some like to have as large as a thread pitch as possible to avoid the muzzle from belling/flaring out. However, this concern is much more academic than it is practical when using cut rifled barrels. More of a potential issue with buttoned barrels.
- You need to have some shoulder, to shoulder up muzzle brakes, suppressors, etc. 0.750" is not a thick barrel, and there won't be much shoulder when threaded 5/8x24. Some, like TacOps, prefer more shoulder engagement. TacOps uses a 9/16x24 thread for their rifles (which have thick barrel contours) to achieve more shoulder engagement.
- Accessory availability. Some threads are more standard than others. 5/8x24 and 1/2x28 are pretty standard. 9/16 not so much. Not a big deal if you plan on sticking with what you ordered, but will be difficult to change muzzle devices in the future.
- Some like to have as large as a thread pitch as possible to avoid the muzzle from belling/flaring out. However, this concern is much more academic than it is practical when using cut rifled barrels. More of a potential issue with buttoned barrels.
- You need to have some shoulder, to shoulder up muzzle brakes, suppressors, etc. 0.750" is not a thick barrel, and there won't be much shoulder when threaded 5/8x24. Some, like TacOps, prefer more shoulder engagement. TacOps uses a 9/16x24 thread for their rifles (which have thick barrel contours) to achieve more shoulder engagement.
- Accessory availability. Some threads are more standard than others. 5/8x24 and 1/2x28 are pretty standard. 9/16 not so much. Not a big deal if you plan on sticking with what you ordered, but will be difficult to change muzzle devices in the future.
Generally speaking, you should always choose the largest thread your barrel can support. Muzzle device options may be a factor in deciding, but most manufacturers support all the common sizes.
You really need a .040" or wider shoulder for suppressors, though, so unless you do a collar, your barrel OD needs to be at least .080" larger than thread major.
A .750 OD .28 cal barrel, definitely 5/8-24.
You really need a .040" or wider shoulder for suppressors, though, so unless you do a collar, your barrel OD needs to be at least .080" larger than thread major.
A .750 OD .28 cal barrel, definitely 5/8-24.
I’ve messaged them to cancel the order and ask them what they suggest and contacted MBM and ask their opinion as well. Thanks for the help on this. Muzzle brakes are a new area for as I have never really used them
Yup. Definitely a deal breaker, especially with so many good brakes out there that are 5/8"x24. I would never deviate from that size muzzle thread unless I absolutely had to. Even my .223 bolt gun is 5/8x24. Make life so much easier and is huge for running suppressors.
This is a handy list of muzzle threads by manufacturer:
https://infogram.com/rifle-thread-pitch-guide-1ho16ve585gv2nq
It's may be not as complete as you might need but it is a start.
https://infogram.com/rifle-thread-pitch-guide-1ho16ve585gv2nq
It's may be not as complete as you might need but it is a start.
I had LRI thread my Rem710 300 winmag (.750), with a 9/16 x 24. And then had Nathan at MBM make me a 4 port 2 piece brake to fit.
Works like a champion, I can honestly say the 300WM feels like me 6.5 CM.
My guess is they didn't feel it would be strong enough. 5/8x24 in a 0.750 OD brake doesn't leave a lot of meat. Others, like X-Caliber, do make a similar brake with 5/8x24 threads.
APA states that .750 is the minimum. Which muzzle brake of theirs is the same. Link it if you can
Have you seen micro bastard? One that's threaded 1/2x28 has a wall thickness of .120". If it were 5/8x24, it would be .065"
I haven’t. But I wanted one so now I need to figure something else out
X-Caliber Progressive profile #1. Choose your options, including specific caliber.
http://www.x-caliber.net/progressive-muzzle-brake
