Check your linkage roller bearing and make sure it's on the pin of the secondary linkage arm. Your rifle butilizes what is called an "articulated" cocking arm,...that is two levers working in unison. Without the roller bearing, the foot at the bottum of the cocking arm,... Where it pushes the piston back,...may in fact be sliding past the pistons cockinf contact area of the slot. Not very likely, but like I said before,.. sometimes weird things just happen!!! LOL's. Whatever happens in the next few hours, just relax and don't get excited!!! At least not too much!! tjk