Primer misfire ?

[pullintoobs]

 I picked up a used Knight from a guys kid that I work with last year.  It was used but never had been shot. I Shot it a few times right after I got it and it shot nice.  Cleaned it up and put it away and haven't touched it until the other day.  Well I was a bit disappointed.  I had some serious issues with the primers not going off all the time.  Like 1 in 5 would work. Is it possible that primers are old? I always thought primers would last a long time. Perhaps I tightened the breech plug too much and  the firing pin was not  striking it with enough force?  As said earlier I had zero issues last year when I first got it.  I  am certainly not confidant to take it deer hunting and have this happening. Any input ?

[lwh723]

Have you had the bolt apart to make sure spring isn’t cruded up.

[pullintoobs]

It does not have a bolt. The trigger assembly drops down. It is an older ML, and probably not the best, but it is what I got. It is Knight Revolution. Figured I would giver this a whirl and see if I really liked it before buying something nicer.And I got this thing cheap as can be. But I did have that out and cleaned it well.

[a1smokepole]

There was a recall on that gun for trigger you my want to check to see if that guns been fixed.
www.krwarranty.com/
what primers or you using and powder