327 FM data calls for small rifle primers in the hotter loads, which could have a heavier primer cup in some brands, resulting in the possibility of a misfire. I reload for mine using Brian Pearce's subsonic Power Pistol load and regular small pistol primers.
Not necessarily, it depends on what source of reload data you look at. Some are just regular spp even for the
"hot" loads
Did the OP ever say what ammo he was using? Factory or reloads??