Just got a 0.177 example of/one of these, in a CS800 stock. Needs a bit of work to tidy up the metalwork but shoots nicely, although a bit "boingy". Now sporting a nice boosted Leup 18-40 EFR

What size piston seal do these beasties take, and what do people who have got inside one of these suggest for a nice sub-12 ft-lb tune to take out the twang?




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