Mossberg 500 trigger issues

[Spud]

I have a Mossberg 500 that I picked up new. I broke the safety block by over tightening the stock bolt. I replaced the safety entirely. My trigger would pull every time when the safety was broke  . Now that I've replaced the safety, the trigger locks up maybe every 5th dry fire. It just locks up completely, won't pull until I rack it again. Ive disassembled/reassembled it several time and can't see an issue. Hoping to fix it myself if I can. Anyone have tips on what I should look at?