I have very good luck with Felix lube, I don't really know if it slings off, the one boolit I did recover went into sandy dirt but it wasn't all caked in the grooves. Meanwhile at the muzzle there is a lube star, and the bore is black and shiny, if I run a patch through it the patch comes out black and greasy so I think it is "seasoning" the bore between shots, leaving behind a residue that lubes the next round fired. Even though these are 310gr GC boolits. Groups are tiny little things.