I resealed a Hammerli Single in the 80s with common o-rings and no problem whatsoever, but this Master work dragged on and on.
First I made two heavier-duty valve tools than I'd made 30 years ago. Then it was difficult to find the (very specific) metric o-rings, but finally found what I needed from a website called The O-ring Store.
After resealing the gun shot weakly, so I started trying lighter (weaker) valve springs and chrono testing after each spring swap. Finally got the velocity up, but would get a couple weak shots in the middle of the power bands with each Co2 cartridge (that may have been heat or refrigeration related). Kept monkeying with valve springs and also lightly moly-lubed the hammer and hammer-spring. FINALLY got great results... after 16 cartridges, over a tin of pellets, and more than a dozen hours!
Stopped counting hours invested once I realized there was no way to charge an hourly rate, and I'd have to chalk up the time invested to a 'learning experience'. But she's now humming along at 430-450 FPS for 50+ shots per cartridge with RWS Meisterkugelns. PHEW!!!
This experience is a reminder why I seldom hire out to work on other folks' stuff, as I'm always very n-n-nervous about messing up someone else's gun. Hopefully this was a character-building experience; my character can use all the help it can get!
First I made two heavier-duty valve tools than I'd made 30 years ago. Then it was difficult to find the (very specific) metric o-rings, but finally found what I needed from a website called The O-ring Store.
After resealing the gun shot weakly, so I started trying lighter (weaker) valve springs and chrono testing after each spring swap. Finally got the velocity up, but would get a couple weak shots in the middle of the power bands with each Co2 cartridge (that may have been heat or refrigeration related). Kept monkeying with valve springs and also lightly moly-lubed the hammer and hammer-spring. FINALLY got great results... after 16 cartridges, over a tin of pellets, and more than a dozen hours!
Stopped counting hours invested once I realized there was no way to charge an hourly rate, and I'd have to chalk up the time invested to a 'learning experience'. But she's now humming along at 430-450 FPS for 50+ shots per cartridge with RWS Meisterkugelns. PHEW!!!
This experience is a reminder why I seldom hire out to work on other folks' stuff, as I'm always very n-n-nervous about messing up someone else's gun. Hopefully this was a character-building experience; my character can use all the help it can get!
