After the circlip is removed deep down the tube of the single shot Rocket, you can be lucky and get the valve to slide out with a knock. The problem is removing the O ring right at the far end of the tube as it is usually stuck fast and gummy. Lawrie uses an aluminium tube with a saw tooth edge to clean out the old O ring. Apparently in the early days Benjamin supplied you with two O rings for the cylinder cap as the material they used expanded with exposure to the CO2 gas and you could not screw the cap back in after fitting a new capsule. They instructed you to fit a new O ring and put the old one to one side until it returned to size after evaporation of the gas so it could be reused. We think the wrong quality O ring was also used for the very back seal which causes it to get all gummy over time.
The Schimel is not a difficult pistol to re-seal. People make a couple of mistakes in assembly which cause them to leak. The chamber cup seals are the same in all of them but there are 4 design differences in the capsule valve unit.
Baz
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