- Location
- Edmonton, AB
I know about the video. seen it many times.
Can you recommend a muzzle brake/flash hider?
- Thread starter Grizz Axxemann
- Start date
I know about the video. seen it many times.
There is a reason most .30 cal brakes are threaded 5/8x24. Because the 1/2x28 thread is WAY too small for a .30 cal bore. Cut a 1/2x28 thread into a .30 cal barrel and you are left with a mere .076" of metal between the bottom of the thread and the bore. Very bad idea.
huh? i'd guess there are a few hundred shorty m14's out there with 1/2x28 threaded muzzles...... surely we would see some issues by now. It's a standard practice and is quite safe I assure you. Cutting an m14 barrel back to 18.5 - 18.75" does not leave much material diameter to cut a proper 5/8 x 24 thread...... sometimes you can make it work but the norc barrels are less than 5/8 at the thread start point and slightly less than that at the thread finish point/muzzle. This is why we do not use that thread as a general practice with our custom builds. YMMV
So cause lots of people do something, it is automatically a good idea? We used to drive without seatbelts and make kids toys with lead based paint but today we know better.
If you think I am full of it, you do the math yourself.
1/2x28 thread starts out with a nominal diameter of 0.5 of an inch. The 28 tpi thread has a depth of .022" on each side of the barrel.
0.500" - 2 x .022 = .456" (minor diameter - between the bottom of the threads on each side)
.456" - .308" = .148" (subtract the bore from the thread minor diameter)
.148" / 2 = .074" (amount of metal between the bottom of a thread and the bore)
Go find a set of calipers or a micrometer and dial in .074" and see if that looks like a safe amount of metal to contain the pressure of a full power .308 Win cartridge.
Just the act of machining the barrel tip down to .500" will cause the bore to expand as a result of removing the metal surrounding the crown.
I am just a newbie, but I assume:
- pressures at the end of a barrel are much less than the pressure exerted on the bolt, for example
- threading the muzzle on the end of the barrel strengthens the end of the barrel, it's a big chunk of metal afterall going over the weaker, threaded part
I guess where it could get dangerous is if the weaker barrel is hit and bent.
It seems to me that the end of the barrel is more prone to bending with the material being so thin (as Suputin demonstrated (.074" isn't much folks!)).
- pressures at the end of a barrel are much less than the pressure exerted on the bolt, for example
- threading the muzzle on the end of the barrel strengthens the end of the barrel, it's a big chunk of metal afterall going over the weaker, threaded part
I guess where it could get dangerous is if the weaker barrel is hit and bent.
It seems to me that the end of the barrel is more prone to bending with the material being so thin (as Suputin demonstrated (.074" isn't much folks!)).
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How about this.
If anyone has ever experienced any issues with their 1/2-28 threaded barrel please post up your experiences here.
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I have... I loaded ammo.. I shot ammo and it made a big boom..... (vortex's seem to do that..)
and down range there were lots of holes in the paper the old computer... the watermelons didn't stand a chance...
If it performs like in the video, hope my score improve at the ranges....
Well got my SEI Navy Muzzle Break from ATR. Installed it in 10 min, nice unit, well built , one inch shorter than the norinco bird cage that was on there.
Next, I need some range time with it. Hope it performs like the video......
Wow, great price for that brake. $190. It's a really good brake, it should be priced even higher! It's performance rocks man....
How about this.
If anyone has ever experienced any issues with their 1/2-28 threaded barrel please post up your experiences here.
Maybe the issue would come from firing a chopped & 1/2-28 threaded barrel WITHOUT flash-hider or muzzle break. Meaning that even if the metal is thin at the crown end after a 1/2-28 thread, a big part of the rigidity actually comes from the presence of the flash-hider.
Just ordered the SEI Navy Muzzle Brake for mine true Alberta Tactical Rifle. Take the old one off and slip the SEI on with the Norinco Metric Nut.
I Saw on the SEI site that this brake is threaded to 5/8 - 20TPI, how did you use the norinco metric castle nut? im new to the M14, just got one. Does it just slip on?
Thanks for clarifying that, i wasn't sure. I like the idea of not having to remove my barrel and have it re threaded to a different size, sounds like a pain to but the barrel back into the receiver and index it correctly. are there any other brakes like this that can use the norinco metric nut/threading? possibly with the front sire dovetail so i wouldn't loose my front site??
You don't need to do any re-thread job. Just simply remove the old muzzle break and install this new one by using old castle nut.
