I have an 8 lb can of Lil' Gun and have avoided using it for .357 Magnum because of the reported problems with barrel throat erosion.

It's original intended use was for reloading .410 shotgun, and so many users have reported severe forcing cone and barrel erosion that it is problematic. I've read that Freedom Arms has advised against using that powder in their revolvers.

For now, at least, I will confine it's use to single shot pistols and rifles.