If you're talking about powder, I'd stick with the manuals. If you're talking about the actual projectile, I don't recall seeing anything over 100 gr, with most being around 90-95 gr. To be effective, there has to be a balance between lighter rounds (faster) and heavier rounds (slower). Heavier rounds tend to penetrate deeper, until velocity becomes an issue. I worry less about weight with the .380 and just stick to ammo from reputable manufacturers. All this would apply for any .380 and not just the LCP II.What is the maximum grain limit for the LCP 2? Also, best FMJ Ammo for .380?