I have to regard the SuperMag and the Maximum as two separate cartridges for several reasons. For starters, Elgin Gates, originator of the 357 SuperMag, regarded them as two distinct cartridges. (If they were to be considered the same, then the obvious correct name would be SuperMag since it was the original and inspired the Maximum.) Elgin advised Ruger and Remington against the 357 Maximum idea, but Ruger did not want to make the frame window long enough for the SuperMag. I have loading data for the two distinct cartridges. It's not possible to get the original performance from the Maximum. The 0.125 inch OAL difference is larger than that between the 38 Special and 357 Magnum. A correctly loaded SuperMag will not chamber in the Ruger. I have some 357 SuperMag brass. Not only that, but I bought it through the IHMSA. It's also headstamped with Gate's name. It was made by PMC. It's a bad batch of brass since it will give very difficult extraction no matter how light the load. (Dan Wesson told me they had the same problem with the same brass and I should switch to Starline.)

The 357 Maximum is a classic example of the big manufacturer's taking a wildcat commercial and being unable to resist fixing what ain't broke. Ala, the 224 Harvey K Chuck to 22 Jet fiasco. That one sullied the reputation of all bottle necked revolver chamberings even though the rest of them (And there were many.) didn't deserve it.

The question gets a bit fuzzy in the case of a single shot since there are no cylinder length constraints.

I had wondered for a long time how long the Seville cylinder was. I've never actually seen one in the flesh and wondered what became of them.

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The Maxo