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Modification to repair FTE issues on Saigas with blocked gas ports


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The hole for the "D" mod in the gas block has nothing to do with the rear sight, they are not even close in proximity. The front sight bead on a factory S12 is attached to the top of the gas block and

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  • 3 weeks later...

This thread was very helpful.

 

I had 4 port gun with all holes exposed. The holes were about 1.5mm. The gun wouldn't cycle skeet/trap rounds, but I found relatively cheap ammo that worked fine (Saga Export 32g).

I decided to drill those holes to 2.0mm to make it more reliable. The pins came out nicely, but the gas block was harder. Shelf bracket didn't do nothing in my case, but a hammer and a brass rod did the trick.

 

Assembly was easier and I got the gas block in the right spot with first try. No problem inserting those pins either.

 

BTW, I used 2mm and 3mm pin punches and it seemed to be the right size.

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  • 3 weeks later...

First, Thanks to everyone. I was able to resolve my FTE problems with the information that has been provided here.

I purchased a used SAIGA 12 last week and experienced the same apparent typical FTE problems with the low power ammo, high brass ammo of all types work fine. Long story short, 1 of the 3 gas ports was almost completely covered. I removed the gas block easily enough using the information found here and modified the opening so that all ports were visible. Completed minor polishing of hammer and bolt carrier. It still failed to extract the low power ammo. As I pondered over what else to do, I remembered a post saying that the UTG Pro Quad handguard had cause problems for some so I removed the handguard and put the factory forearm back on. This corrected the problem. I’m assuming that the gas tube was being torqued enough that the gas piston could not move freely.

If I had used the KISS principle and removed the add-on handguard first and test fired, I may have saved myself some time and effort but it was a good learning experience.

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  • 3 weeks later...

This thread is good for explaining how to remove the gas block. However, I think most of us would agree that most of the time the D cut is a bad idea. Keep it minimal and do the minimum to uncover the ports.

 

Ports are either blocked or not. You definitely don't want to enlarge that hole to the point where it reaches the shoulder next to the threads.

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  • 1 month later...

Just finished this mod. Brand new gun with 4 gas holes. None of them were partially not drilled and only two were partially block by gas block. Got everything off drilled main hole to 11/32 and drilled gas ports to 5/64. Still getting 100% fte on Winchester 1oz loads. 1 1/8 cycle just fine. Before the mod the bolt was only opening about an inch and a half. Now it's almost ejecting them just barely catching on the end. I have done the bolt drop test and looked at my piston and everything is in spec. Should I drill out the gas ports one size larger or should I try a after market plug and puck?

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well i went around town and bought evry different type of low power shells i could find. the only thing it wont eat is the 1180fps winchesters. one thing i did notice is while i was shooting some of the 1200fps winchesters i turned the gas plug to setting one just to see what it would do. it cycled just fine. think i may be over gassed so i ordered the auto plug and a css puck. since its shooting well next step will be conversion and some furniture. got two 12rd mags coming in and about to get a 20rd md drum. really injoying this gun.

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  • 1 month later...

I would like to say thank you so much to jeffD for this thread, I have had so much trouble with My S-12 and its FTE. I have up graded every part of the rifle so far, and its still not working. I got on here last night saw this thread and started to read, and took out my gas plug and puck and at first I could only see 1 hole, then after looking better, I could see almost 3 holes, and believe it or not the holes are not even drilled through the barrel, they are only 1/2 way in. so there is no holes working on this thing. ; ( Unreal!!! I converted the rifle my self, so I am hoping with this thread maybe I can fix this my self and not have to pay someone to do it. so again thank you.

Edited by harleyc
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Yes this entire thread helped me out quite a bit too. I posted a different thread about my problems (FTE on some Bulk Low Brass) and what I did to fix them. Here is the cliff notes version of that thread:

  • 4-Port Gun.......all 4 ports came drilled at 1/16th or 0.0625
  • Gas Block partially covering 2 of the 4 ports
  • Removed Gas Block - enlarged gas block hole to 5/16th or 0.3125 (some are doing 11/32nd or 0.34375)
  • - - - - - - - - - -This uncovered one of the partially blocked ports (3-o-clock on images below)
  • Drilled all 4 ports out to 5/64 or 0.078125 (widely posted on these forums as the baseline for a 4-Port gun)
  • Filed away just enough material (did not do the D-MOD.......did just enough material) on the gas block hole to uncover the 12-o-clock port (on imaged below) that was still blocked after enlarging the gas block hole
  • This solved all of my FTE problems on every kind of low brass I can purchase with the exception of the bulk Winchester Super Sport stuff that is only 1oz shot, 2.75 DRAM, and runs at 1145FPS however by doing all of the above cut the FTE I previously had on Super Sport ammo almost in half
  • - - - - - - - - - - My real solution to the weak Winchester Super Sport problem for now is I do not buy this kind of bulk anymore. Sticking with stuff that is 1 1/8th oz shot, 3.0 DRAM, and runs at 1200FPS or better (Winchester Universal and Federal Bulk are both this) and have zero issues. These cost the exact same price as the lesser powered Winchester Super Sport Bulk so it is a no brainer to not buy the weak Winchester Super Sport that has problems cycling in $2000+ off the shelf hunting semi-auto shotguns.

 

post-47413-0-61056600-1369612763.jpg

 

 

post-47413-0-89209000-1369612761.jpg

 

-bp

Edited by burntpowder
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  • 1 month later...

Yes this entire thread helped me out quite a bit too. I posted a different thread about my problems (FTE on some Bulk Low Brass) and what I did to fix them. Here is the cliff notes version of that thread:

  • 4-Port Gun.......all 4 ports came drilled at 1/16th or 0.0625
  • Gas Block partially covering 2 of the 4 ports
  • Removed Gas Block - enlarged gas block hole to 5/16th or 0.3125 (some are doing 11/32nd or 0.34375)
  • - - - - - - - - - -This uncovered one of the partially blocked ports (3-o-clock on images below)
  • Drilled all 4 ports out to 5/64 or 0.078125 (widely posted on these forums as the baseline for a 4-Port gun)
  • Filed away just enough material (did not do the D-MOD.......did just enough material) on the gas block hole to uncover the 12-o-clock port (on imaged below) that was still blocked after enlarging the gas block hole
  • This solved all of my FTE problems on every kind of low brass I can purchase with the exception of the bulk Winchester Super Sport stuff that is only 1oz shot, 2.75 DRAM, and runs at 1145FPS however by doing all of the above cut the FTE I previously had on Super Sport ammo almost in half
  • - - - - - - - - - - My real solution to the weak Winchester Super Sport problem for now is I do not buy this kind of bulk anymore. Sticking with stuff that is 1 1/8th oz shot, 3.0 DRAM, and runs at 1200FPS or better (Winchester Universal and Federal Bulk are both this) and have zero issues. These cost the exact same price as the lesser powered Winchester Super Sport Bulk so it is a no brainer to not buy the weak Winchester Super Sport that has problems cycling in $2000+ off the shelf hunting semi-auto shotguns.

 

post-47413-0-61056600-1369612763.jpg

 

 

post-47413-0-89209000-1369612761.jpg

 

-bp

 

My real solution to the weak Winchester Super Sport problem for now is I do not buy this kind of bulk anymore. Sticking with stuff that is 1 1/8th oz shot, 3.0 DRAM, and runs at 1200FPS or better (Winchester Universal and Federal Bulk are both this) and have zero issues. These cost the exact same price as the lesser powered Winchester Super Sport Bulk so it is a no brainer to not buy the weak Winchester Super Sport that has problems cycling in $2000+ off the shelf hunting semi-auto shotguns.

 

= WIN! :)

 

Don't feed her what she don't like and she will be your best friend. red_heart.gif

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  • 2 weeks later...

Have a 4 port S12.  Drilled out the ports with 5/64" drill bit and drilled out the gas block hole with 5/16" drill bit.  Cleaned up all burs with fine sand paper.  Most of the 4 ports were open in the gas block hole but drilling it out to 5/16" opened them up very clear.  No filing was required.

 

This gun also has the Tac 47 Auto gas regulator, as well as bolt polish.  The gun now shoots cheep Walmart Federal 3 Dram, 1 1/8 oz shot, 7 1/2  shot ammo with zero failures.  Before the shell would not start to eject, just be pinned in the port.  The Tac 47 Auto gas regulator is nice because I do not have to adjust anything now to shoot high brass ammo.  The Tac 47 will just bypass the excess gas.  It really works.

 

The process to remove the gas block is not that hard.  I used Gunk Liquid Wrench "Super Penetrant" around the gas block.  Soaked for 1/2 hr.  After I got the block started it moved with little effort.

 

In another post some one stated that they took a punch to mark the gas block and the barrel so it would make re-alignment of the block easier.  I suggest that you do that as well as scribe the position of the block prior to start of removal.

 

I am a Happy S12 owner now. biggrin.png

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  • 2 weeks later...
  • 4 weeks later...

I'll be a knuckle head and ask. I read thru a number of threads on here and searched a few times but no luck.

 

I'm purchasing a S-12 from a shop here local. I have not fired it and plan to before tearing into it. Is there a list or general idea or the range of serial numbers that have these issues? Also, how are you guys getting the build date from the serial numbers. My serial is number HO8448844. Thanks guys and gals.

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My H08 was a vodka special. I would do it again, though. Yours is about 30,000 or so after mine. Maybe they changed the drill bits to the right size somewhere in there. The polish and port job had it running fine and I did it myself.

Edited by Yeoldetool
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  • 2 weeks later...
  • 4 months later...

Air chisel is the way to go. I ground the 1" wide chisel flat. I had a chunk of aluminum plate I put between the chisel and that flat piece on the GB, started with zero air pressure, pulled the trigger with a good steadied grip, had a friend feed in air until I had a good controllable pounding, lol  30 seconds later the GB was off. I have a lathe so I polished that area a bit with some 2000 wet and dry sand paper. I use a piece of 1 1/4 pvc to pound it back on, it went back on nice and snug, and came off with less effort the second time.

You can buy the Chinese junk air hammer set from Harbor Freight for 10-12 bucks, it works fine for jobs like this, I would buy one of those if you want one to last.

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  • 2 months later...

  Hi. I hope this helps some people on taking off the gas block on the S12. If the pins are being stubburn, spray some WD40 on the 2 pins and let it soak for 5-10 min. Then use one of those small metal phillips head screwdrivers as a punch and using the brass hammer. I have both pictured with the Punch set that the brass hammer came in and the small screwdriver pointing to to pins that need to be punched out and what side. I used the largest brass punch with the brass hammer and brass punch to knock off the gas block by alternating sides while hammering. Some of the brass punch might deform and break off some bits of brass but should do the job. Gas block came off after about 5 min of doing this. Just reverse the steps to get it back in. Hope this helps.

post-12381-0-37441600-1403256032_thumb.jpeg

Edited by kripp
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  • 2 months later...

My bottom pin will NOT come out, even after soaking it overnight with Liquid Wrench (well, it's actually Blaster, which I've heard good things about) and using a bigger hammer than most. Does anybody have any additional suggestions? 

 

I can knock the top one around pretty easily, but that bottom one is a BEAR.

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  • 3 weeks later...

My bottom pin will NOT come out, even after soaking it overnight with Liquid Wrench (well, it's actually Blaster, which I've heard good things about) and using a bigger hammer than most. Does anybody have any additional suggestions? 

 

I can knock the top one around pretty easily, but that bottom one is a BEAR.

 

 Bigger hammer and better punch. It will come.

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  • 5 months later...

I finally did this, pretty straight forward.  I kept putting it off because I couldn't get the pins to come out.  Broke 2 Starrett punches and finally resorted to a Craftsman.  Bent it about 20 times before I read someone's post here about cutting the punch down.  I cut 1/2 of it off and it worked like a charm.  Used a regular hammer and after about 5 hits, it came out.  The rest was easy.  Used a dead blow hammer to tap the block back on.  I've got a 3-hole that wasn't even 2/32".  Opened them up to 3/32", hope to get it out and test it in a few weeks.

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