I owned one of S&W's first run of 8x.38 Super revolvers and I was bitterly disappointed with it. It would not function at all without moonclips and mine keyholed with every size, shape, diameter and weight of cast bullet I ever tried. It was very particular about which powder I used and any powder that left behind any fouling caused all kinds of extraction problems which then quickly led to chambering problems. As far as I could tell, its single purpose was for winning ICORE matches, which are shot at 120 PF with lots of reloading. As an added insult, brass that had been fired in .38 Super Open autos generally would not fit into the cylinder after sizing. I found one load which functioned perfectly and gave excellent accuracy, but I did not like the narrow range of application and traded the gun away. That was the best trade I ever made.
Nowadays the eight shot .357 Magnums can be loaded with .38 Short Colt in Starline brass with Hearthco moonclips. This setup is so good that it makes the .38 Super revolvers obsolete. The Super revolvers are not worth the money and headaches. Most shooters that I knew that had the Super complained about them even more than I did, though most of their problems were quality control related. This always was a remarkably inferior product for an expensive Performance Center item. S&W was alleged to have used .357 barrels with .355 cylinder throats (hence the poor performance with cast bullets) though I never slugged mine to verify it. I was happy to get rid of that revolver and I have since bought an eight shot 627 in .357 Magnum. The Magnum is a far better revolver and much more useful, versatile and practical.
Dave Sinko