#1 - DO NOT fire fmj loads to clean out the lead. What a perfect way to destroy your barrel!
#2 - Bullet fit is most likely the cause of your leading. All my 9mm"S I shoot .358 or .359 through with no lleading. Air cooled wheel weight material.
#3 - Bullseye powder has given me the best of results through many 1000"s of rounds.
#4 - Use a good lube. Lee Liquid Alox on any style of bullet works well for me.
Mid range loads always seem to work the best with best accuracy for me.