Razorback 72 Posted June 3, 2010 Report Share Posted June 3, 2010 (edited) My Saiga S-12 IZ-109 19" shotgun has a really loose rear sight block./gas tube. On the Saiga parts sheet it is part #4. It is listed as tube with end piece. I drove out the factory dovetail v sight for replacement and after I was finished, my rear sight block /gas tube was loose. The movement is side to side, and I would like to ask for assistance to figure out how to permanently, or at least semi permanently tighten it back up. I have plans for the existing dovetail slot on the rear sight block/gas tube, but it won't work unless it can be made to line up with the centerline of the barrel, and have no movement. Thank You to all who reply in advance. Edited June 4, 2010 by Razorback Quote Link to post Share on other sites
Razorback 72 Posted June 3, 2010 Author Report Share Posted June 3, 2010 (edited) Bump, any one else ever experienced this before? Edited June 3, 2010 by Razorback Quote Link to post Share on other sites
Cobra 76 two 2,677 Posted June 4, 2010 Report Share Posted June 4, 2010 The only thing that holds the gas tube tight is the backward pressure exerted on it by the gas block. The rear part of the gas tube that has the dovetail groove cut into it, is notched into the trunnion. I have seen them before that were loose. Somehow you must have hit it hard enough to loosen the gas block, just enough to let the pressure off the tube, letting it rattle loose. First I would try making sure the gas tube base is centered. Then I would remove the stock, place the square end of the receiver on a 2x4 wood block, on a cement floor and using a big hammer (if you don't have a press) and a hardwood or brass (or aluminum....something hard but softer than steel) block, or large punch, and knock (or press) the gas block straight back (downward with the muzzle pointing straight up)....applying the pressure or strikes to the front of it (gas plug removed), as close to center as possible. It should only take a couple of sharp whacks with a hammer (or a little pressure from the press ram). 2 Quote Link to post Share on other sites
TonyRumore 1,332 Posted June 4, 2010 Report Share Posted June 4, 2010 There are some guns that are like that, and like Cobra said, the gas block is not pushed back far enough. Unfortunately, the cross pins for the gas block have already been drilled and you are pretty much stuck with it. You could knock out the pins, push the block back, redrill the cross slots and re-pin it, but if the press-fit of the block to the barrel is not tight enough, under recoil, the block will creep forward and the problem will reappear. The simple solution.....just buy a bottle of #690 LocTite wicking compound and put a few drops on the tube where it meets the receiver and you will be done with it. Tony Rumore Tromix Corp 2 Quote Link to post Share on other sites
Razorback 72 Posted June 4, 2010 Author Report Share Posted June 4, 2010 Man, You guys rule!!! +1 to Tony and Cobra 76. I had thought about if it could be drilled and pinned, or if i could use an adhesive , but didn't want to drill it, and was worried about the heat causing the adhesive to release. Tomorrow it will be tight. A tremendous Thank You to both Tony and Cobra for your assistance. I owe you both. Here is what I have going on. I am having the final rear catch parts machined , so I just mounted a cheap sight on it for the pictures. I'll put my EoTech 551 and Troy Ind BUIS on it once the catch is on, and the block is tight. Hiding under the Chaos quad is a Cobra gas tube shield, and 8 parts from Tromix here and there. Thanks for the parts and the Technical assistance guys. Quote Link to post Share on other sites
TonyRumore 1,332 Posted June 4, 2010 Report Share Posted June 4, 2010 What in the hell is that crazy looking flip up top cover? It looks like a top cover on a belt-fed. Tony Quote Link to post Share on other sites
Cobra 76 two 2,677 Posted June 4, 2010 Report Share Posted June 4, 2010 Sweet build man. Quote Link to post Share on other sites
Razorback 72 Posted June 4, 2010 Author Report Share Posted June 4, 2010 (edited) Well, it's just a highly modified Chaos extended top rail turned abound backwards and then machined to fit the hinge I had made. I was looking for a way to mount a rail for my optics, but I couldn't seem to be able to find one. I was looking at the extended rail and the light bulb went on. I wish it was belt fed. It looks that way because I haven't installed the dust skirt in it yet.Thanks for the assistance Tony. After I finish this Flat Top S-12 project, I would love to start working on a belt fed S-12 flattop. I came your shop about a month ago, but I didn't realize you were closed on Saturdays. I owe you in a big way. Edited June 4, 2010 by Razorback Quote Link to post Share on other sites
corbin 621 Posted June 7, 2010 Report Share Posted June 7, 2010 The simple solution.....just buy a bottle of #690 LocTite wicking compound and put a few drops on the tube where it meets the receiver and you will be done with it. Tony Rumore Tromix Corp Thanks Tony. My Saiga 12 has had a loose sight block since I got it. I'll have to try the 690 and see how it works. Corbin Quote Link to post Share on other sites
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.