Everyone of you need to read hksmiths remark: "The only difference between .38 special and .357 brass is the .135" that they add to the case to prevent .357 ammo to be loaded into a .38 special." Over, and over and over, until you understand it! There is no difference in strength between .38 Spl. and .357 Magnum cases with the minor difference of lot-to-lot variation!

The volume difference between .357 Magnum and .38 Spl. cases when loaded with the same 158 gr. bullet to the same seating depth, is approximately 15%! A .357 Magnum load reduced by 15% will give approximately the same pressure level and be just as safe. It will not give the same velocity as the expansion ratio also changes.

OP is talking about reduced .357 loads, not full pressure! In essence we are in the .38-44 pressure range now or it isn't enough less to be considered "reduced". By the time you get to .38-44 loads you are in the range which S&W at one time approved for use in the then new 2" Military & Police, ca. 1935-1940. While definitely high by current SAAMI +P standards this is not dangerous!!!!!

No question that if a 25,000 PSI .38 Spl. was fired in a standard steel frame K-Frame or even J-Frame revolver it will be quite startling to the shooter, and probably painful, but it will not result in catastrophic damage to the revolver!

And for this remark: "....watch for signs of pressure...." you can forget this! Even with Magnum handgun loads the first "pressure sign" you are likely to observe is small pieces of steel raining down around your ears! Handguns, revolvers or not, are not rifles and do not operate anywhere the pressure levels. You can blow up any handgun without even the classic "flattened primers" showing anything at all to be alarmed about. If you do not understand this you better quit handloading until you do, before you either hurt yourself of destroy several hundred dollars of firearm. Any handloading manual will tell you that there is no such thing as "pressure signs" loading for handguns!

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Gunsmithing since 1961