Saiga 12 project: gas system

The factory-standard Saiga 12 shotgun is designed to shoot “Hi-Brass” loads, the smallest loads that will function reliably are #6 shot as opposed to the softer-shooting and more commonly used ”low brass” #7.5 shot found at Wal-Mart. Every gun is different, but if our Saiga is fed anything smaller that #6 shot, not enough gas will be vented from the barrel to cycle the action fully. This combined with a super heavy recoil spring results in the shell not ejecting fully, and no shells are fed in from the magazine. That causes a jam that looks like this:

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Imagine the dummy shell is a spent shell. There wasn’t enough gas cycling the action to push the bolt all the way back, the recoil spring started to push the bolt forward with a shell still on it and it hit on the top of the chamber.

Luckily lots of places make upgrade parts for the Saiga 12. To make it function with low-brass loads, two parts have to be replaced. The stock gas adjustment knob has two settings, one for Hi-Brass birdshot and the other for slugs and buckshot. Swapping the factory made knob for one that allows more gas to come back and cycle the action. The other part is the front recoil spring. The factory spring is very heavy and won’t let the bolt come far enough back to eject the shell.

To rectify these issues I bought the Carolina Shooters Supply Low Brass Reliability kit. The kit consists of an aftermarket gas adjustment knob (The online page says it’s a Gunfixer 4-position, but mine came with an MD arms 5 position), an ETAC TwisterPuc (more on that later), and a Carolina Shooters reduced power recoil spring.

To install the adjustment knob and TwisterPuc, you first have to remove the factory adjustment knob. This is done using the adjustment tool supplied with the gun from the factory, or any long and relatively thin piece of metal will work:

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Push down the detent with the tool and unscrew as though adjusting


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Once you get past the detent you can unscrew it by hand.

After unscrewing the gas adjustment knob, the old gas puck should fall out into your hand. If not, take a cleaning rod and push the puck out from the receiver.

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The Izhmash factory gas puck.


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The ETAC TwisterPuc.


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Install the TwisterPuc with the flat side down:


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Now screw your aftermarket adjustment knob in:


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The MD arms plug has 5 settings, + letting the most gas back and – letting the least.


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There are 10 settings, one on either side of the knob to account for random thread start on the Saiga. To run birdshot, use the + setting to start, then go lower to reduce recoil until you get a jam.

Now that you’ve done the gas system, changing the recoil spring is easy. Pull the factory spring off the guide rod and replace it with the reduced power spring.

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Now take your Saiga to the range and blast away! It should run Remington and Federal #7.5 shot Value Packs fine, but Winchester Universal is iffy.

If your Saiga won’t run the 7.5 shot at all, you’ve probably got an improperly drilled gas port in the barrel. That means that when Ivan Ivanovich built your Saiga at the Izhmash factory, he forgot to drill all four holes in the barrel where it vents into the gas block. Take your Saiga to a gunsmith with experience with Saigas.

This entry was posted in 3-Gun, Gunsmithing, Photos, Saiga, USPSA and tagged , , . Bookmark the permalink.

2 Responses to Saiga 12 project: gas system

  1. Dad says:

    Good post. Let’s do some video of it shooting next time out at the range.

  2. Harold says:

    Just to be clear – looking at the gas adjustment from your photo – clockwise to increase gas pressure? Thanks
    (Found out more from you than anybody).

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