7.62x39 gas block - Page 1

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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.

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.

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.

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

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.

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.

Posted: 6/15/2015 5:24:54 PM EDT

[#6]

Quote 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.

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.

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.

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.

[ARCHIVED THREAD] - 7.62x39 gas block

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