I have stocked and am preparing to rust blue a Sako AV that is still in the white after around 30 years. I am stumped re. disassembling the striker assembly to blue only the checkered shroud and have been unable to find any useful schematics or other documentation. The owner's manual diagrams and Beretta customer service are not useful. A bit more force might be the answer but things feel like there may be a mechanism trick and I would prefer to know the facts from someone that knows before I break a probably very hard part on an unused action.

Here is where I am. The striker assembly is removed from rest of the bolt. Four parts (there may be an as yet hidden part like a key) are obvious in the assembly: (1) spring, (2) striker rod/firing pin, (3) shroud, and (4) inside the closed shroud a "whatever" nut/sear piece threaded to the aft end of the striker. With the spring compressed toward the firing pin and held in place, the shroud is freely moves fore and aft almost 1/2" as limited by contact with the "whatever" and freely rotates a few degrees either way as hard limited by the "whatever". So, without spring pressure the shroud is loose, retained on the striker/firing pin by the "whatever" functioning as a nut. The "whatever" thread is completely loose and will freely rotate a few degrees either way before stoping hard (in both directions) against some form of interior obstacle possibly a hidden key on the striker shaft some trick in a keyway. Possibly the thread is just jammed and more force will do the job. But it sure doesn't feel that way. But I've "fiddled" the easily moving parts seemingly every way without finding a hint of the trick.

I understand that you must ultimately unthread the "whatever" to disassemble the assembly. What I do not understand is if some form of trick mechanism is what is preventing the apparently quite loose thread from completely spinning free. Of course, the issue could be just some hidden metal burr.

Any help from someone that really knows the Sako AV would be much appreciated before I get frustrated and apply enough torque to break something.