I shot N320 for a while; 5.2 grains with a 200 gr SWC, either cast or plated, did ok. A friend tried it with 185 grain JHPs (5.9 grains, as I recall) and got occasional off rounds. Some just sounded strange - he would stop and look as though it might have been a squib, but it never was - some gave short recoil malfs. This was prevalent enough that he shot ball at the IDPA Nats because he did not have time to redevelop loads with another powder. I would not use it with bullets lighter than 200 gr. Actually, I don't use it at all any more, back to 700X for a common powder in 12 ga and almost all non-magnum pistol ammo.