Let me point out something that others have mentioned. Firing cartridges in chambers not designed for them can result in catastrophic failure and injury. SAAMI pressures are based on firing a cartridge in the chamber designed for it, so that's not a good basis if you are talking about firing the cartridge in a different chamber than what it's tested in. I am not familiar with the chamber dimensions of the .38 super vs. .38 spl/.357 Magnum, and it is possible that it is close enough to .38 Spl/.357, however, unless I had an expert on both to tell me that they are close enough to be interchangeble, I simply wouldn't do it.
We Americans have a tendancy to get cartridge confused with caliber. .357 Magnum is a
cartridge, .357 is a
caliber. It appears that the .38 Super (sometimes referred to as the .38 Super Automatic) is much like the 9x19 with caliber of .356. But bullet size isn't going to make it safe for a chamber, if you have excess space in a chamber, a weaker cartridge can develop enough pressure to blow up a stronger cartridge's chamber. And here's another problem, it may work okay a few times, but one day, the metal will give. An good example is the M-1 Garand. Firing slow burning powder cartridges through it will eventually bend the operating rod and possibly allow the bolt to impact against the rear of the frame causing eventual catastrophy. The M-1 chamber itself is robust, but the gas system is not and was designed for certain loads to be fired through it. Same for a revolver or any weapon, just because it doesn't explode the first time, doesn't mean it won't eventually. The .38 Super was not based off the .38 Spl case like the .357 Magnum so that's a different design; it was designed based on the .38 ACP, a completely different
cartridge, and it was certainly never designed to be fired in a revolver (chamber).
Not adhering to cartridge designs can have pretty severe results. I think most will agree that you should only fire ammuntion through firearms designed to fire it.
If it were me, an old Colt chambered in .38 super would be the answer; just having the ammunition would make me want one.
