If there is still a copper filter in the asa or duckbill, remove it. These get fouled over the years and reduce operating pressure.
Also, try firing it with your hand over the mouth of the barrel. Sometimes old spyders require the back pressure to recock.
Another thing to try is removing the expansion chamber and running gas directly into the marker. This can help narrow down the issue.
Edit: after looking at the pic of the bolt, you have ALOT of wear from friction. The wear and whatever caused it can cause improper cocking. Maybe try a delrin bolt? If you are interested I have an ACS (anti chop bolt) new in package i'd sell ya cheap. However no promises this will resolve the issue.
The o-ring you put on the hammer, you said it was a red one, but was it for a modern hammer or a 'fatty' hammer. This WILL cause the issue you are having. I have both I could include with the bolt free.
To see if it's a 'fatty' hammer, just see if it fits down the barrel. Fatties don't
Last edited by melkson; 06-09-2012 at 08:45 PM.