I had trouble using this stuff in a Mini-30. I would get a misfine every third or forth round. I think they use extra hard primers to compensate for the lack of a fireing pin return sprin in SKS's etc.
I bought about 20 boxes of this stuff.
I got similar results. 1 in 5 or so would not go off. I think hard primers too....and I was also using a mini 30.
Oh well....guess I will use it as practice ammo and pull the duds.
What a waste.