Hey guys, so I took my armalite M15 into my local gunsmith to get a flash hider and muzzle threading installed. The threads are tight and lock up fine but they have a slight upward cant to them causing the hider to become crooked. Is there anyway for me to get this fixed or is my barrel pooched now?
Any way to fix improper muzzle threads?
- Thread starter TK-Hryciuk
- Start date
lejarretnoir
CGN Ultra frequent flyer
- Location
- 162km from Connaught
Short of cutting them off and rethreading, but then you have a shorter barrel which may change legal requirements and if chrome lined presents another problem.
Restricted would still be restricted, but it is an upper which is not tracked.
Doesn't matter if it is restricted or not. Cut below the magic number and the firearm becomes prohibited.
The barrel cut below the limit is not illegal; nor is the upper with the cut barrel installed; but assemble this upper/cut barrel combination on a lower, and the result would be a prohibited firearm.
As for as the threading problem, check the flashider. As mentionned, it might be the problem. If it isn't, new threads would need about 1/2" of barrel.
Pretty hard to cut the threads crooked with the barrel set up properly on a lathe - that's why checking the flashider should be the first thing.
lejarretnoir
CGN Ultra frequent flyer
- Location
- 162km from Connaught
tiriaq is correct about the lathe setup threading, but I've seen barrel threads cut with a die that were crooked. The only way to check that FH is to try it on another barrel or chuck either the barrel or FH on a lathe and check for straightness.
Best to ask your smith how he did it and bring it back to him.
Best to ask your smith how he did it and bring it back to him.
True but too many idiots think they can run a die on and cut threads that way. If the OP described the threads as "tight" that would make me suspect this "smith" did use a die instead of single pointing the threads.
If the threads are really not straight there is no solution but to cut them off and try again ..... I would suggest with a different smith as the original one is a doofus.
You know, I never even considered that a gunsmith would try to thread an AR with a die.
I've seen barrel threading die setups advertised for DIY muzzle threading which use a bore fitting guide rod and a die holder to try to keep the threads co-axial. Just asking for trouble.
Either the flashider or the muzzle is out of whack. If it is not the attachment, best find another 'smith.
I've seen barrel threading die setups advertised for DIY muzzle threading which use a bore fitting guide rod and a die holder to try to keep the threads co-axial. Just asking for trouble.
Either the flashider or the muzzle is out of whack. If it is not the attachment, best find another 'smith.
Like others have said, if it is the barrel threads that are crooked, take it to a different "smith" to fix it. He either didn't set it up properly to thread it, or used a die. Either one is just not worth giving them a second chance.
Try another muzzle device and see if the problem remains. If it does then you are probably looking at cutting and rethreading. For that you will want to get a "licensed" gunsmith to fix it. But, as has already been pointed out, you are entering into a sketchy part of the law there.
Try another muzzle device and see if the problem remains. If it does then you are probably looking at cutting and rethreading. For that you will want to get a "licensed" gunsmith to fix it. But, as has already been pointed out, you are entering into a sketchy part of the law there.
So good news guys, returned to my local gunsmith and showed him the problem. Took a straight edge to it and deduced that the threading was proper to the bore but the barrel itself was somehow bent, how? I don't know, but he gave me a brand new dpms 14.5" with factory installed threading for no charge. Replaced the old one in my upper and had it all back together within an hour.
Probably took the barrel off the receiver and used the 3 jaw chuck to thread the barrel, if he used a lathe at all. Of course as soon as you center point it then anything of the sort becomes quite obvious.
And there is nothing wrong in using a die to cut nuzzle threads if you have the proper tooling and skill to do so...
- Location
- East ontario
Sorry i call BS on that , your "smith" screwed up and CYA by getting you a new barrel.
Ive seen barrle blanks that are 20thou off center and still the flashider was no problem,seen barrels bent allmost an inch to one side still no issue.
bbb
Upon reflection I think your smith is BSing you or he is a real clown. How exactly is it possible to determine that an external thread is straight to an internal bore using a straight edge?
Even if the bore is not straight to the outside of the barrel it is quite easy to produce threads that are concentric to the bore.
It is nice that you are getting a new barrel out of it but I would make sure it is in fact a new barrel and not some piece of crap he has lying around the shop.
Even if the bore is not straight to the outside of the barrel it is quite easy to produce threads that are concentric to the bore.
It is nice that you are getting a new barrel out of it but I would make sure it is in fact a new barrel and not some piece of crap he has lying around the shop.
