357 magnum is accurately named. The bullet is approximately .357 in diameter. .38 special comes from an earlier era when calibre naming conventions were creative, and mostly based off of black powder conventions (such as ".44 magnum" actually being .424 or so). The .357 magnum is actually a child of the .38 special in that there was a load called .38-40 HD that came about in the 20's which was, in essence, a .38 special case loaded to .357 magnum pressures, and was designed to be fired only in guns that carried the .38-40HD designation.
Well, needless to say, if it fits in a gun, people will shoot it, so there were quite a few .38 special handguns destroyed by use of .38-40HD rounds being put through them. The ammo and gun manufacturers got together and decided to correct the problem by creating a round that was the same overall dimensions as the .38 special with the exception of being 1/8th of an inch longer, thus preventing it from beign chambered in the .38 specials of the day.
Smith & Wesson was the revolver maker involved with the ammo manufacturer (Remington? I know they made the .44 mag, but I am not sure if they made the .357) that created the round, and they produced the M-27 to handle the load. There is still debate over where precisely the "magnum" designation came to play and who named it such. Nonetheless, the round and revolver was a spectacular success, and was the single most popular choice for law enforcement in rural areas for quite some time. It is still one of the best manstoppers in production.
It is perfectly safe to fire .38 special round in a .357 magnum gun, and many people practice shooting this way as it is far less expensive than magnum ammo. It is also perfectly safe to use .38 bullets in a .357 magnum case as well, as they are precisely the same thing (.38 special loads tend to be lighter grain weight, but that matters little).
The only performance penalty, beyond the expected lower velocity of the .38 special, would be the increased distance between the bullet and the forcing cone. Proper accuracy in revolver relies heavily on the forcing cone. That 1/8th inch isn't much, but it can be significant if you are looking for truely precise shooting. For the average joe though, there is no appreciable difference aside from velocity.
I googled away and there you go... the whole shit.. and send it to the dude that fucken wanksta that made that pic.
Still love you Rob.
