What size should gas ports be on a 24 inch 2 port gun?

[greekjeep 1]

Just wondering if any one knows how big ports should be on my 24 inch saiga, I've been told that 2 ports are common on that length barrel. But even after some polishing and a low brass reliability kit it still won't cycle the shells all the time. It is better than before but not perfect.

Thanks for any info 

[goldenpony 61]

I never heard of a 2 port gun.

[pedal2alloy 206]

The longer the barrel, the less port area that is needed due to the extended time the wad is between the ports and the muzzle, resulting in an increased amount of gas energy.

 

You could drill them a little bit bigger, or add a 3rd of the same size

[greekjeep 1]

Well I removed the gas block and enlarged my two ports haven't shot it yet, question if that doesn't help how bad of an idea would it be to drill a third port after without removing the gas block. It was not easy to remove the first time and not sure if I want to remove it again. I've seen guys drill ports in the opposite angle before with good results, I'm just not sure if one port in the opposite angle would cause things to get gunked up in the gas puck area? Thanks again

[pedal2alloy 206]

The enlarging may fix the problem.  If it doesn't, drill a 3rd port but do it with the correct angle

[JohnnyE 81]

I have a 24" barrel, 2 port gun, 2009 production. I'll try to measure the ports tonight. It received a Pauly Glass Bolt polishing, Tapco FCG (with profiles hammer), etc. Gun eats everything I feed it, 3 dram skeet loads through magnum slugs.

 

You'll see a common theme from the pros around here. Be very careful about making changes that can't be undone. Make sure your BCG and hammer are worked over before you start enlarging holes.

[JohnnyE 81]

OK, I opened the gun safe and here's what I found.

 

24" barrel, 2-port, 2009 production Saiga 12. One port measured 0.093", the second measured between 0.070" and 0.080". Thinking back a few years when I did the conversion and had Pauly do the Glass Bolt, I drilled one of the ports to 0.093", then thought I should stop right there, put everything back together, and test the gun before doing any more drilling. Gun worked fine, so I left well enough alone. That tells me the factory ports were, yes, between 0.070" and 0.080". YMMV.

[lbsrdi 1,078]

Be very careful about making changes that can't be undone.

Make sure your BCG and hammer are worked over before you start enlarging holes.

[greekjeep 1]

Thanks for everyone's help after I hit the range I'll post on how she worked out.

Thanks again

[greekjeep 1]

Well it's been a while since my last post and I finally shot my saiga after enlarging the two ports. 

Pleased to say she cycles perfect now. Its nice to know with everyone's help here and not being afraid to follow the advice that was given I could get the results I wanted.

Thanks again

[lbsrdi 1,078]

Very good, a properly functioning S12 is hard to beat.

[evlblkwpnz 3,418]

From my experience with the 24" S12s, 2 at .078" is about perfect if everything else is as it should be (the action). The ports in the 24" S12s that I had were very small from the factory, .067-.070" IIRC.