hi everyone, i just spent an hour trying to get the gas piston to move freely thro0ugh the whole length of the tube. i've been firing corrosive ammo and cleaning the gas tube with hot water and then with regular cleaning methods. the rufle has been sitting for few weeks since i ran out of ammo, and i just checked up on the gas tube to make sure its ok, and it ain't. when i try to insert the piston into the tube the wrong way (wider head first) it only goes to a couple mm before the 2 vent holes. thats where the head of the piston sits when assembled. i know there must be some rust there but i cant believe that its enough to keep the piston from getting past that point. i cleaned it to infinity, and then took a drill to it to try to file some of the rust oft the inside. it still doesnt look like there really anything in there that should be holding the piston back, but it just won't move past that point no matter what. i dont really want to insert the piston in and take a hammer to it, but i'm getting desparate and frustrated. any suggestions? i'm running out of options here....
sks gas tube clog??? please help!
- Thread starter serbian
- Start date
use a .40 cal brass or steel brush that you don't plan on using for anything else ever agian... lubricate with clp, and scrub like a mofo...
and if you're using water after shooting, use something like wd40 after the water....
and if you're using water after shooting, use something like wd40 after the water....
well, i used a 1/2 drill bit on the inside of the tube to no effect, so i dont think a .40 brush will do much. and i dont see how the tube could've been bent while in storage...i'm pretty perplexed about this. yes, the piston fits head first into the thick part of the tube, all the way untill the thinner part where only the piston rod can fit. the head of my piston gets stuck just short of the 2 venting holes in the thicker part of the tube. this would stop the piston from moving all the way back to syscle the op rod and the action. my next move would be to go get a box of ammo and try to put a round through it and see if that will get the piston past the invisible obstruction. does anyone think this is dangerous? any other suggestions? thanks andy and jjwelin for your input, much appreciated.
serbian said:
Don't use a power tool with a drill bit to do this... This is going to take time and elbow grease... The oil will do most of the work.
I wouldn't try to put rounds through the firearm until it is operating correctly.
serbian said:
my 2 sks pistons do not travel all the way down the tube either, with the pistons in proper position, one piston protrude about 1 1/2 " and the other 1 1/8" thru the back that strike the piston extension, i have no rust but yet something prevents it from going all the way, probably narrowing of the tube due to heat.
i would guess there is no need for the main piston to travel all the way back bcos the piston extention without the spring only travel 3/4" so travel all the way would be pointless. so check out how far your piston extension travel with out the spring compared to your main piston.
as far as cleaning concern, use a bigger brush and wd40, like jj suggested, i use an old 12g shotgun brass brush, it works great, fits perfectly.
- Location
- Not really sure.
Yea this is the same with my Yugo, about 1 3/8 mine protrudes.curtton said:
It still works flawlessly though, I figure they are mostly likely designed so.
hmm...really? i figured the holes were there to let any leftover gasses escape after the piston head has passed them. i drove 45 mins today to get some ammo so im gonna see how it cycles with the restricted piston movement tomorrow. if it works as flawlessly as it did when the piston could move all the way, i won't bother doing anything to it...not that i know what to do to it anymore anyhow. if there are problems, i might have to order a new gas tube. anyone know of a good place to get a gas tube? marstar has pretty much every other sks part lister, except the gas tube.... are there other canadian retailers that carry sks parts? once again, thanks for all the input guys. if it wasn't for this forum, i'd be in the dark.
- Location
- Not really sure.
yea it has to be corrosion, what else could it be?. I mean the gas tube on my yugo has pretty thick walls, you would have to wack her hard to dent it, even slightly. I think it would just mark the surface before caveing in. I always use #9 solvent to clean my sks parts, and WD40 with .40 cal brush, plus Qtips to get the little nooks and crannies of the port from the barrel to the gas tube.jjwelin said:
After everything is squeeky clean I add lightly some Fluid film, which is made from wool wax, and tends to impregnate any oxidization you have in the metal permenatly stopping it.
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doc25 said:
I don't believe the holes are over pressure ports. The holes are there to allow the piston to move freely when the gas tube is pressurized. With out the holes the air behind the piston would provide resistance and not allow the piston to move easily! I also don't believe the piston should move past the holes. If anyone has a piston that moves past the holes in the side of the gas tube please let me know! The piston travel only needs to be about 1.5 inches or so...enought to kick the bolt back but it does not need to push it all the way.
Serbian, I think your gas tube is just fine and I think you will find that it works properly. Please don't ruin your gun by taking power tools to it to clean it. I think you might end up doing more damage than good. My gas tube and piston works just the same way as you have described...seems to get stuck about 1.5 inches in....I think that's OK and is by design.
Let us know how it works out with the fresh ammo!
