Its worth noting that this hole in the cylinder can stretch when big springs have been fitted. Im sure there are people on here who can weld them up and redrill but just dont fit a powerful spring. Meteor springs seem a better fit in hawks than hawk spring Ive tried recently and the Diana 25 spring remains a soft plinkers option. Release pressure on cylinder and end cap and mainspring should come out. Ease piston out. These had a ptfe washer rivetted on (Nibbs sells them ) But I prefer a leather one held by a screw and nut. SEE THREAD "hawk mk 1 info" post 13 by DCL DAVE. Thats the sort of thing I did. Lube up and put back together. Piston in and then mainspring and push down on cylinder the same as in stripdown to replace end cap and pin. Place sear and searspring on safety catch and slide into housing,locate,put pin in and circlip on. Fit trigger spring onto trigger with long leg behind trigger and locate,pin and circlip. (if your cylinder pin hole is worn and cap is a little off the cylinder, you may have to use a piece of shim steel to cover the gap to stop trigger spring going into it whilst you are replacing it. Replace cam in breech and replace circlip. Replace barrel and secure. GO TO NEXT POST