Real BP, T7, and Shockey's all clean up with water and soap. I don't understand why you don't want to use BP? Water will not hurt your barrel as long as you keep it lubed after cleaning. Most all sidelocks are cleaned with water.

Another option is Pyrodex P. It ignites easier than T7. I wouldn't shoot Shockey's if you paid me, so I have no advice for that crap.

I'll ask again. Are you using musket caps? If not, and you're using #11 caps. The Remington caps are hotter than some of the others, but your gun is suppose to use musket caps. I'd use those.