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 How short can I cutting down 16" Barrel?
fredr1980  [Member]
12/23/2011 5:28:20 PM
I've searched for a while and can really find an answer to this but how short can I have a 16" barrel cut down for a pistol build before I start running into issues? The only reason I'm going this route is because I want to do a pistol in 7.62x39 (I already have a ton of ammo, reliable mags and another 7.62x39 AR) but can't find any 7.5" Barrels although there is an abundance of 16" barrels. I know I'll be limited by the length of the carbine gas system so cutting it down to 7.5" probably will be a no-go but when would the AR pistol start running into performance issues running a cut down 16" barrel? Also if anyone knows where to get in-stock 7.5" 7.62x39 AR barrels that would be great!

Thanks,
Fred R.
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TCBA_Joe  [Team Member]
12/23/2011 6:01:21 PM
10" seems to be the minimum length for using a carbine length gas system. Just be advised that the as port will also need to be opened up to the appropriate diameter for the length.

Shorter than 10" should be run using a pistol length system.

I will say cutting the 16" to 7.5" might bring the front of the bbl back behind the carbine gas tube, which would make the whole prospect easier. As long as you open up the gas port properly I'd think you'd be ok
fredr1980  [Member]
12/23/2011 11:02:27 PM
Originally Posted By TCBA_Joe:
I will say cutting the 16" to 7.5" might bring the front of the bbl back behind the carbine gas tube, which would make the whole prospect easier. As long as you open up the gas port properly I'd think you'd be ok

Thanks, didn't think about it that way. I would imagine that a heavy barrel would be needed vs a m4 profile barrel to cut it down to 7.5" so as to have the extra material needed to mount the gas block.

Thanks again,
Fred R.

ArmedNAlabama  [Member]
12/24/2011 9:52:29 PM
CLICK
fredr1980  [Member]
12/25/2011 2:26:53 AM
Originally Posted By ArmedNAlabama:
CLICK


LOL, won't be cutting my own barrel down. Actually found a place locally that can cut down a heavy barrel down to 7.5" and redrill the gas port. Still be easier/cheaper to just buy a 7.62x39 7.5" barrel from somewhere if anyone know's where I can get one in stock.

Thanks again,
Fred R.

Mad-Machinist  [Member]
12/25/2011 10:00:00 AM
I know I've built a shorty AK with a 3 inch barrel.....including chamber....LOL soon as I get a 7.62 x 39 chamber reamer and headspace guages.....I'll see how short I can go........how short do you really want to go?
vincentvega6  [Member]
12/28/2011 8:26:16 PM
too bad citadel doesn't have their pistol barrel in stock, and I thought they used to have a 10.5" 7.62 ar barrel? im on the look for one of those for one of my many pistol builds I currently have going.
fredr1980  [Member]
12/30/2011 1:23:33 PM
Anyone know the specs on a 7.5" 7.62x39 barrel with regards to the diameter of the gas port? Probably will be having a barrel cut down and just wondering if anyone out there have those specs. Please let me know.

Thanks again,
Fred R.
fredr1980  [Team Member]
1/5/2012 3:53:17 PM
Well I found specs on gas port sizes for a 7.5" pistol barrel and they range from 0.056 to 0.091... I think I'll split the difference and go with 0.072, another popular gas port size for this barrel length, and just get an adjustable gas block and tune the gun from there. My next question is does anyone know or can measure for me where on the barrel is the gas port with relation to the end of barrel's extension, barrel doesn't have to be cambered in 7.62x39 just needs to be a barrel with a pistol length gas system? I've searched but can't find anything on this. The gun smith cutting the barrel down for me has never worked on a pistol length gas system so he needs the specs on where exactly the gas port needs to be drilled.

Thanks again,
Fred R.
iNeXile556  [Team Member]
1/5/2012 6:31:59 PM
pistol gas port is at 4.7"
fredr1980  [Team Member]
1/5/2012 7:54:57 PM
Originally Posted By iNeXile556:
pistol gas port is at 4.7"


Thanks, I was finding different distances while searching ranging from 3.5" to 6" ... good to know it's 4.7".

Thanks again,
Fred R.
fatkid35  [Member]
1/6/2012 7:01:55 PM
http://www.marksarmory.com/7_62x39_barrel_pistol_barrel_7_62_barrel_p/7.62pistolbarrel.htm

fredr1980  [Team Member]
1/6/2012 9:07:55 PM


Yeah, I actually called them a couple weeks back and the lady stated that they were backordered for at least 2-3 months... They are one of two places that I was able to find that carried 7.5" 7.62x39 barrels and both were out of stock with eta's of 2-3+ months, one actual removed the barrel from their site after telling me the eta. I'm getting a 16" heavy profile barrel I aquired recently cut down to this length next week. Thanks all for the help on this.

Fred R.
youngsait  [Member]
1/11/2012 11:58:46 AM
Try and call Model1 Sales, They will also customize your pistol.

http://www.model1sales.com/index.cfm?fuseaction=category.display&category_id=395
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