I have a pre-ban MAK90 -- has standard "US" parts (trigger,furniture, etc ) for 'compliance' (wanted pistol grip). This has been a great rifle -- always working flawlessly.
However, the other day at the range, two things happened that had never happened before:
1) The trigger failed to 'reset' --- After firing a round, it cycled and properly loaded a new round in the chamber, but the trigger was not reset -- I had to manually cycle the action to get the trigger reset. The trigger is a double hook tapco trigger group; not an 'adjustable' trigger.

On a guess, I removed the buffer pad that was installed -- although it didn't interfere with manually cycling, nor had it ever been a problem in the past, but thought I'd pull it off to see -- it seemed to fix the 1st issue, but I can't explain why -- so it could have been coincidence...

and 2) I had two slam fires. I had never had this happen before. pulled the trigger and two rounds fired off (the guy next to me didn't even hear that it fired two rounds it happened so fast)

Which brings us to my questions:

Is the firing pin supposed to be "loose" in the bolt, or should it have some sort of spring keeping the firing pin held back until the hammer sends it flying?

What could cause the two issues? It would seem to me to be "one thing that's wrong" since both issues are new, and happened on the same day.

Is it "normal" to happen once in a while? Neither have happened in the 20+ years I've owned it (bought it new); and in the 10 years it's been "modified" -- but I could believe it's a normal bit, but would like to know that it is. The trigger reset failure is the more distressing issue.

Could it be that the buffer bit is to blame for the trigger issue, or was it more likely to be coincidence?

Could it have been the ammo? All I had with me was some "sellier & bellot"; which I don't recall having shot previously...

And while I"m asking questions -- the gas rod, that is riveted to the slide -- it's a bit loose -- should it be loose or should I have it tightened up?

Thanks for your thoughts & time.

Cheers
-josh