The cartridge has enough space for a full size .357 load. As I said, it is 1/10 longer than the .38 special case to prevent it's being loaded in revolvers not strong enough to handle the pressures. There is, or was a load called the .38 +P+. It is a .357 load in a 38 Special cartridge. There was a federal agency (Treasury, as I recall) that didn't permit .357, but identical ballistics were obtained from the +P+ load. I seem to recall they used the S & W L Frame. K Frame will also handle the .357 just fine.
Do you recall the .357 Maximum, by the way. I never knew the case dimensions, but it was a very hot .357. Sadly, it was in production before it was discovered how bad gas erosion of the frame could be. Hot, and corrosive gases were slicing the top of the frame, so the cartridge was discontinued. If you find such a gun, especially unfired, it is a swell collector's item. I vaguely recall that a Ruger single action was offered, maybe in the Bisley configuration.