Try the shotgun stuff instead since i know you have some scatter guns. They offer the gel too.
http://www.brownells.com/.aspx/pid=1...UN-WAD-SOLVENT
I just use copper cream a few times a year and ive never noticed sabot fouling. You seldom even here about it in smokeless muzzleloaders shooting much hotter powder but im sure it can happen. Things like blowing/drilling a sabot have to be leaving some melted stuff in there.