[ARCHIVED THREAD] - Question on threading a barrel

Posted: 7/12/2005 11:42:18 AM EDT

Hey guys, I found a machinist who can thread the barrel on my AR. I have a Phantom FS that I'm putting on. Is there anything specific, like demensions, that I need to tell him? Or should any competent machinist know what size threads and how long to make them? Thanks in advance...

Posted: 7/12/2005 11:45:50 AM EDT

[#1]

Thread pitch is 1/2" X 28 TPI.

Thread length is 5/8" from the end of the muzzle.

A good machinist should be able to take it from there.

Posted: 7/12/2005 11:46:39 AM EDT

[#2]

Thanks Mongo, appreciate it!

Posted: 7/13/2005 4:57:09 AM EDT

[#3]

can a barrel be threaded at home using a 1/2x28 die ??

Posted: 7/13/2005 5:04:15 AM EDT

[#4]

Quoted:
can a barrel be threaded at home using a 1/2x28 die ??

Almost all barrels need to be turned down to 0.498" on a lathe before you can cut threads with a die. You also need a thread guide to ensure that your threads start square to the bore.

Posted: 7/13/2005 5:39:02 AM EDT

[#5]

Quoted:
Thread pitch is 1/2" X 28 TPI.

Thread length is 5/8" from the end of the muzzle.

A good machinist should be able to take it from there.

yep

Posted: 7/14/2005 5:45:53 AM EDT

[#6]

Quoted:
Quoted:
can a barrel be threaded at home using a 1/2x28 die ??

Almost all barrels need to be turned down to 0.498" on a lathe before you can cut threads with a die. You also need a thread guide to ensure that your threads start square to the bore.

that is what i thought, but wanted to ask.., thanks for that .498" info !!

Posted: 7/14/2005 5:48:13 AM EDT

[#7]

I cnouldnt find a machine shop anywhere around here that even had the 1/2x28 die.

Posted: 7/14/2005 5:54:38 AM EDT

[#8]

I sent two uppers to Compass Lake Engineering to have their "de-Clintonizing" package. One was one of their CMP uppers with a Krieger barrel and the other was a Bushy 16". They threaded the barrel, replaced the front sight with one with a Bayonet lug and installed a flash suppersor for $125 each which includes return shipping and insurance. There may be cheaper places but I wanted it done right. BTW they look great.

Bill

Posted: 7/14/2005 5:57:56 AM EDT

[#9]

Quoted:
I cnouldnt find a machine shop anywhere around here that even had the 1/2x28 die.

It's a NEF (national extra fine) die, not very common and usually a special order item.

Posted: 7/14/2005 6:31:49 AM EDT

[#10]

Quoted:
I cnouldnt find a machine shop anywhere around here that even had the 1/2x28 die.

Then send the barrel out to ADCO or AR15Barrels.com both do good work and have decent turn aournd times.

[ARCHIVED THREAD] - Question on threading a barrel

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[ARCHIVED THREAD] - Question on threading a barrel

[ARCHIVED THREAD] - Question on threading a barrel