A few months ago I purchased a used Impact Mk2 (.25 cal) with the old Power Plenum and Huma air regulator. The gun shot well and had no major problems until recently. When I tried to increase the regulator pressure from 160 to 180 bar to shoot heavier slugs, the needle on the fx regulator pressure gauge wouldn't move at all. After loosening the regulator screw half a turn, I stopped increasing the pressure and let the gun sit for a while. The needle was still at 160 and nothing had changed. After bleeding the airgun, I set the regulator pressure back to its original position, refitted the air cylinder (filling pressure about 200 bar) and left it untouched overnight. The next day I unscrewed the air cylinder to see what was going on, but there was a continuos resistance to it half the way on the thread. Just before unscrewing the cylinder, I suddenly heard a loud crack like a popping balloon or blown seal from the gun.
After screwing the bottle back on, I checked the pressure gauge on the back regulator valve and it showed a fill pressure of about 100 bar, even the bottle pressure gauge was still about 200 and the regulator was set to 160.
I disassembled the gun and checked all the common seals, but could not find anything unusual. After reassembly, I turned the regulator set screw all the way in and attached the air cylinder. While slowly releasing air into the empty plenum via the regulator set screw, I heard hissing and air coming out of the muzzle, which stopped after the set screw was backed out enough. Even with pressure building up, the regulator gauge remained at 0. I replaced the gauge with a Wika gauge and was able to increase the pressure to previous settings (air still escaping when too slowly released into the plenum). I also found that the bottle valve was leaking slightly when left unscrewed and ordered a new valve as well.
What could possibly be the source of the loud bang, should I be worried or was it just the pressure gauge blowing up?
How can unscrewing a airbottle cause something to blow up in a airgun? (Using only silicon based airgun lubricants)
Is the airleak from the barrel normal on low pressure when refilling an empty plenum? (I checked all O-rings on the valve house/ valve stem no apparent damages)
After screwing the bottle back on, I checked the pressure gauge on the back regulator valve and it showed a fill pressure of about 100 bar, even the bottle pressure gauge was still about 200 and the regulator was set to 160.
I disassembled the gun and checked all the common seals, but could not find anything unusual. After reassembly, I turned the regulator set screw all the way in and attached the air cylinder. While slowly releasing air into the empty plenum via the regulator set screw, I heard hissing and air coming out of the muzzle, which stopped after the set screw was backed out enough. Even with pressure building up, the regulator gauge remained at 0. I replaced the gauge with a Wika gauge and was able to increase the pressure to previous settings (air still escaping when too slowly released into the plenum). I also found that the bottle valve was leaking slightly when left unscrewed and ordered a new valve as well.
What could possibly be the source of the loud bang, should I be worried or was it just the pressure gauge blowing up?
How can unscrewing a airbottle cause something to blow up in a airgun? (Using only silicon based airgun lubricants)
Is the airleak from the barrel normal on low pressure when refilling an empty plenum? (I checked all O-rings on the valve house/ valve stem no apparent damages)
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