i use it mostley for break barrels, you put one rubber clamp over the jaws where the barrel goes and then you put a small piece of broom handle against the sping end, then put the other end of the clamp on, you squeeze the trigger and every pull pushes the broom handle into the gun, taking the pressure of the retaining pin!
Sounds complicated but it really isnt
Lee
AA S400 .177/Hw95K .22/BSA Lightning .22/QB78 .22/2 x BSA Meteor .22/BSA Cadet .177/ SMK B2 .22 and .177/Slavia 625 .177/Baikal IJ38 .177/Diana Model 25 .22/Diana Model 1 .177