My .22 cal Bowkett-tuned FWB Sport was running a little hot so I opened it up today and removed a coil from the spring and one of the preload washers.
The rifle is one JB modified in the 1980s and has a screw down breech lock and barrel shortened at the breech. The cylinder is from a 124 but the barrel is a .22.
Some of you might be interested to see the piston seal mod. It has an O ring sset in a stiff red plastic washer screwed into the end of the piston. The other end of the piston has been rounded at its edge and highly polished. The spring guide is floating as pictured.
The gun shoots very sweetly with very little felt recoil.