Quote Originally Posted by T 20 View Post

Next up is piston weight back down in the 270s with factory 33 coil Spring.

This will give an indication of what power can be achieved with a Protek synthetic seal conversion kit and a factory Spring for the folks without a lathe.
With the "Original/Diana" factory 33 coil Spring with 276 gram piston, chrono results were :-

Hobbies = 580fps

Superdomes = 500fps


So I stripped the gun again and weighted the piston back up to 305 grams and put the 28 coil Spring back in but added 4mm of extra preload to see if it would lift the power a tad, results :-

Hobbies = 610fps

Superdomes = 590fps



So the tune I've now chosen to go with is the 270gram piston with 28 coil HW95 Spring with 16mm total preload that gave 11.6ftlbs with Hobbies.

11.6ftlbs will do me for a bit of paper punching in the garden and dealing with the occasional rat.



All the best Mick