When I competed in round ball m/l matches I was very serious about every component of my load. I cast my round balls then weighed them for consistency, I used teflon coated pillow ticking, I sifted my black powder and I used one brand of caps ...........RWS. My belief was that the hotter the cap the better the ignition. We tested different brands of caps by how far they would lift a dime off the muzzle of a longrifle. 25-30 years ago RWS was the best. IDK about now. But, I've still got a stash of RWS caps.