I think gun club are the same as sts & black hulls. one thing i like to do as well as compare base wad apperance, is to compare hull capacity. I use #9 shot and fill one hull to the top, then pour it to the hull i want to compare to. You can get a pretty good idea if everything will stack up right. Ive had good results this way, but still dont know exactly where my pressures are at. Hope this helps- Tad.