GAS BLOCK VENT HOLE

[crucified 2]

i recently switched over to the KVAR hand guard.

the gas block vent hole is exposed when using this hand guard, whereas it was covered by the stock hand guard.

does this affect pressure in the gas block at all or should it function essentially the same?

my S12 has run flawlessly thus far but i know some people have tig welded this vent hole shut in the past to increase gas pressure.

Just curious as i've not had a chance to fire it yet with the KVAR unit.

 

the arrow points to where i'm talking about:

 

 

here's where i've seen it welded shut:

Edited September 10, 2010 by CRUCIFIED

[Paulyski 2,227]

DON'T DO THAT!

It's a dump vent & it doesn't add any pressure for cycling, but it's there for a reason.

Yeah, many of us have seen that tutorial.

[crucified 2]

yeah i figured it was there to bleed off excess gas,but it does seem like the stock hand guard plugs that hole pretty damn good!

[Frosty 9]

I have read that exact same tutorial/bubba job. That particular S12 lost half of its life span due to that hole welded shut. Everything was fine right up to the welding of that hole.

All that time.

All that concern over blueing.

All that work to convert.

All that WASTED.

 

Frosty

Edited September 10, 2010 by Frosty

[Cobra 76 two 2,677]

yeah i figured it was there to bleed off excess gas,but it does seem like the stock hand guard plugs that hole pretty damn good!

If you look at the inside of a factory HG on a gun that's been fired a lot, you can tell it's not actually blocking anything. There will be burnt looking carbon deposits there and sometimes even an indentation from the hot gasses melting the plastic away there. This also proves it should be left alone to do it's job.

 

Yeah Frosty, people shouldn't try to reinvent the wheel unless they are better informed.

[Paulyski 2,227]

I have read that exact same tutorial/bubba job. That particular S12 lost half of its life span due to that hole welded shut. Everything was fine right up to the welding of that hole.

All that time.

All that concern over blueing.

All that work to convert.

All that WASTED.

 

Frosty

The member is still here & He says the gun runs well... but the Russian engineers wouldn't add another production step if it wasn't beneficial.

This is an example of someone doing everything they read & think of at one time, rather than tuning the gun till it's dependable & then stopping.

It's like going crazy on the ports all at once rather than up-stepping until it runs well.

Going too far is tempting if one lacks a close place to test-fire between mods.

[crucified 2]

very enlightening!

my s12 has run flawlessly thus far.

just figured i'd throw the question out there to get a general consensus on the vent.

on a brighter note,the KVAR hand guard is friggin' awesome!

VERY well built and quite sexy as well!

Edited September 10, 2010 by CRUCIFIED

[BobAsh 582]

The hole vents only after the necessary kinetic energy for cycling has already been realized. Don't plug it.

[Shadoh 16]

I just figured it was there so that it would vent out the side of the gun rather than down the tube, keeping crud out of your gun. If it wasnt there wouldnt it vent down the tube just as well?

[evlblkwpnz 3,418]

The hole vents only after the necessary kinetic energy for cycling has already been realized. Don't plug it.

 

In other words, the carrier has already started moving rearward before that gas goes out the exhaust port.

 

Every Kalashnikov based weapon I have ever owned has some sort of exhaust porting. From the Polytech Legend to the Romanian Draco. I look at it this way, there are plenty of other things that do not compromise the integrity of the original design and will increase reliability if done properly. In a nutshell, adequate barrel porting and addressing friction issues WILL make them run well if done properly and there is nothing seriously 'wrong' with the weapon. All 3 of mine run great, but it was along road. They all have factory exhaust porting and run off of Federal Multi Purpose and Winchester Universal. In the tutorials I have seen here, there are some great ideas that are well excecuted, great ideas that are poorly executed, and bad ideas (however, few). Pluging the exhaust port falls in the 'Bad Idea' category. We all mean well.... and there are reasons some things that may seem to be logical have not been done on a wide scale.

[evlblkwpnz 3,418]

nevermind....

Edited September 10, 2010 by evlblkwpnz

[cb8180 2]

The gas block vent is there to reduce the back pressure against the puck. If you think about it, when the bolt is closed there is probably some resistance caused by the closed system. I'm not saying that it's completely airtight but not exactly free flowing. If you take the plug out and push the puck in as far as possible you can't see any sign of the vent hole--this means it simply allows the puck to move as freely as possible, thus improving reliability! Don't try to seal it!