years ago when I first got a revolver and used lead bullets I ran across a few threads from someone who had shot PPC. He said that it was typical to lubricate bullets using oil cup grease sticks from Ford engine grease cups. also said to use a thin coating inside the barrel, just give it a day to film over.
Have not tried that, but using a thin coat of lithium grease on the tips of loaded rounds does great for the barrel insides, but nothing for the forcing cone.
And with spear 158 grain swc for 38s, they need some help despite the film lube speer uses. Despite the fact that they have a make believe cannelure on them, just how do you go about lubing up swaged bullets that don't have lube grooves