It's the sear spring come off or the rear grip screw. I've serviced thousands of spyders and this happens alllllllllllll the time.
ETEK 3LT, with 14" Ti boomstick and cure 3 + bolt F/S
Vanguard creed eyes, membrane, bolt pin, detents F/s[/color]
Old school angel poppets/cup seals, spring detents(not sure which models) F/S