SSS dumps its tank with heavier projectiles
Hey,
I have problem which appeared after I got new tank to my GunPower SSS caliber .22.
Namely, my gun dumps its tank with one shot. The pressure drops from 190bar to 80 or even to zero, if I’m using heavier slugs than JSB pellets. JSB exacts shoot supersonic….
Gun never did any dumping with its original tank. But with new tank, my gun empties its reservoir like a norm, if I’m using heavy . It happens always it with heavier .22 projectiles (even JSB monster could dump the tank). And all this happens when the power wheel is on 3 or 4.
Has anyone else experienced that annoying effect? What in earth could cause it? I have never experienced the same with any other gun.
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Hey zepeteus,
I did the same thing with my top hat set screws. Tried the super glue trick, but no luck. Finally drilled the set screws using a drill bit just a bit smaller than the threads. Worked great. Didn’t mess up the top hat threads. I did this with the top hat removed. If you try this with the stem in, I’d be sure to measure carefully, and put a stop on the bit so you don’t drill into the stem. The screws are short, don’t have to drill far. I had already ordered another vavle from AF before I tried this, so if I screwed it up, no big deal. I ordered an extra 5 pairs of set screws since the are so fragile. I also ordered a quality allen wrench for the set screws. Cheap ones tend to strip the holes. Good luck.
You are probably going to have to take the valve off the bottle and increase the tension on the valve spring
Dave
Polishing didn’t help to that dumping thing. Gun still uses almost all air in one shot.
But polishing helped to me see that the brass screw that holds valve on its place probably somehow locks the valve open. There are some marks, scratches on polished valve stem, and these scatches tell that valve gets somehow violently jammed or stucked there… So, that valve does not shut when bullet leaves the barrel, but stays open, until it somehow slides over the hardest part.
I have to try to get that brass nut or srew open, though it seems to require some special tool….
And, unfortunately I could not lower the top hat. Allen screws on tophat are glued… didn’t know that, but learned that the hard way. Now those allen srews are rounded…
return spring weight- tension?
even less preload?
lower the tophat?
Zepeteus :tag:
A polished valve stem is a good place to begin.
I can’t remember if I used a very light silicone lube on it or not. Some younger expert will jump in here eventually.
I do remember doing a lot of pumping at first. When I had a CO2 dump I had a 3 foot jet exhaust for several seconds until I thought to unscrew the tank slightly..with air I had one dump because the tank wasn’t screwed in properly.
When your tank goes completely empty does the valve just flop back and forth ❓
It is supposed to have some spring tension to help close it. Sometimes the nut that holds the valve return spring comes loose. It can be a tough job to get the tank valve out to check it.
Keep us informed how your doing and check back for one of the gurus to chime in.
I polished valve stem, and will test if that helps.
Maybe it’s the brass part in the bottle (which is in contact with valve stem). I mean, maybe it’s the brass which is left too rough or it not round… but I hope polishing the valve stem could fix the problem.
I have new 39 grain .22 mold (from NEI hand tools), and I sure as hell want to test how those shoot.
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I got new valvestem with tophat, and I installed it. Of course I did little grinding first. Opened those holes so that air could go straight without angles
Gun is finally working fine.
Top hat is set quite low… but gun is still pretty stout.
Thanks for help, everybody.