Warning

 

Close

Confirm Action

Are you sure you wish to do this?

Confirm Cancel
BCM
User Panel

Page AR-15 » AR Pistols
AR Sponsor: bravocompany
Site Notices
Posted: 6/10/2015 2:19:02 AM EDT
Wondering how many folks had to switch to an adjustable gas block with their x39 pistol because of over gas issues?

I'm putting together a 7.5" and already have a nonadjustable gas block sitting around I can use, but will pick up an adjustable if it is usually necessary.
Link Posted: 6/10/2015 6:10:51 AM EDT
[#1]
Well if I had a standard one sitting around taking up space, I would use it as it is easy enough to change out if an adjustable is really needed.
Link Posted: 6/10/2015 8:59:31 AM EDT
[#2]
More people run into under-gassed issues with the x39 builds. The Russian round doesn't have the same pressure as the Itty-bitty NATO pill. The larger .30 cal diameter barrel also consumes a lot of pressure in comparison to the .22 cal barrel.
Link Posted: 6/11/2015 12:22:29 AM EDT
[#3]
A 300blk max load data is almost 3gr less than 7.62x39 using 1680, so I'm expecting more gas with the larger charge if everything else is the same (bullet weight, powder type, barrel length, gas port diameter/length).  My 300blk in 7.5" has plenty of gas, but I don't really want to tear it down to measure the port size to compare.

I'll try the std gas block first and see how it goes.
thanks for the replies
Link Posted: 6/15/2015 7:22:14 AM EDT
[#4]
I had a 7.62 x39 7.5 " pistol. it was definitely over gassed. it destroyed the plastic end of an heavy buffer i had put in. i put an SLR Rifleworks adjustable gas block and a good brake on it and it really tamed it. still loud as hell though, of course.
Link Posted: 6/15/2015 3:52:57 PM EDT
[#5]
Thanks Swandiver... that's inline with what I was expecting. I imagine if you added a brake, it would really be loud. Did you try a linear comp or blast diverter? It should help reduce noise for the shooter.
Link Posted: 6/15/2015 5:24:54 PM EDT
[#6]
Discussion ForumsJump to Quoted PostQuote History
Quoted:
Thanks Swandiver... that's inline with what I was expecting. I imagine if you added a brake, it would really be loud. Did you try a linear comp or blast diverter? It should help reduce noise for the shooter.
View Quote



I no longer have the upper, but i didn't mind the noise. those around me did, however. i liked the recoil reduction.
Link Posted: 6/19/2015 12:41:11 AM EDT
[#7]
What kind of brake were you using?

I have a Kineti-Tech on my 300blk and 6.8 and it has a shroud that can be screwed on when your on the line in a crowd.



Link Posted: 6/19/2015 3:33:44 AM EDT
[#8]
That's why I built my 7.62x39 pistol with a 10.5" barrel with a carbine length gas port. No over gassing issues and it's much less of a flame thrower.
Link Posted: 6/30/2015 1:30:32 AM EDT
[#9]
Modified the GB I had to be adjustable now... only cost $0.75 for a screw, lock washer and nut.


Page AR-15 » AR Pistols
AR Sponsor: bravocompany
Close Join Our Mail List to Stay Up To Date! Win a FREE Membership!

Sign up for the ARFCOM weekly newsletter and be entered to win a free ARFCOM membership. One new winner* is announced every week!

You will receive an email every Friday morning featuring the latest chatter from the hottest topics, breaking news surrounding legislation, as well as exclusive deals only available to ARFCOM email subscribers.


By signing up you agree to our User Agreement. *Must have a registered ARFCOM account to win.
Top Top