[ARCHIVED THREAD] - 9mm Barrel/Chamber Print

Posted: 10/14/2011 3:30:46 PM EDT

Has anyone got a print for chamber end of 9mm barrel for AR?
Using Colt/RRA bolt style

Thanks

Posted: 10/14/2011 10:52:37 PM EDT

[#1]

Cut it the same as a 556 extension,,,, and be sure to have the flange at least 0.135" thick at a minimum... bore hole for a 1/8" index pin, and chamber it with a 9mm reamer and use a common 9x19 round as a gauge with it to stick out end of chamber face at least 0.126" to 0.135" (this will handle the occassional shorter factory ammo that one might come across)..

I do not have measure for angle of opening to chamber, as barrel I had cut from blank ran with a flat face at chamber end... other factory barrels I have been refaced to correct the headspace, not re-adjust chamber opening, and run fine.

Posted: 10/14/2011 10:54:56 PM EDT

[#2]

Thanks very much
I figured as much but wasnt too sure if the 'extension' length as such was the same as 556

Cheers

Posted: 10/15/2011 5:35:34 AM EDT

[#3]

"stick out end of chamber face at least 0.126" to 0.135""

Is that dimension taken with the rear of the barrel still being perfectly flay/square, or taken after the angled cut it done? I assume from flat.

I hope that question makes sense to you.

Posted: 10/15/2011 2:47:15 PM EDT

[#4]

Quoted:
"stick out end of chamber face at least 0.126" to 0.135""

Is that dimension taken with the rear of the barrel still being perfectly flat/square, or taken after the angled cut it done? I assume from flat.

I hope that question makes sense to you.

I did have to read slowly, but it did make sense.. from the flat face of barrel end.

When you make the angle cut, be extremely carefull to not expose anything above the web of the case... the barrel in the pic was cut with square chamber opening, and fed from a Hy-Tech block with plain Uzi mags.. replacement barrel I bought has the angle cut, though reduced due to having to face the end of barrel to get the headspace where I wanted it.