The Great Recession

So the above photo has two Smith & Wesson rimfire revolvers, built probably about thirty years or so apart. The top one is a .22/.32 Heavy Frame Target, an I-frame revolver built probably sometime in the late 1920s. The lower one is a Model 34 Kit Gun, dating to the late '50s and built on the Improved I-frame.

If you look at the cylinders...specifically the rear of the cylinders...you will notice a difference. If you pop open the .22/.32 Heavy Frame, the rear of the cylinder looks strange to anyone accustomed to Smith & Wesson rimfire revolvers, because the charge holes are not recessed to accommodate the rims of the cartridges.

This was actually the norm at the time. Dating back to its earliest revolvers, the teeny little No.1 from before the Civil War, rimfire .22 Smiths had simple charge holes bored straight through the cylinder.

In 1930, however, Remington released new high velocity loadings of the .22 Long Rifle round and, when used in these revolvers, blown case heads were a very real possibility. So when Smith & Wesson released a .22LR version of their K-frame Target, known as the "K-22" or "Outdoorsman", they resorted to a solution that had been used on cartridge conversions of percussion revolvers: a rebated recess around the charge hole to support the rim.

By the mid-1930s, this had migrated from the K-22 to other rimfire Smiths. Here's the cylinder of the Model 34 Kit Gun:

Along about the time that Smith was adapting their rimfire revolvers to handle this new high-pressure, high-velocity .22 load from Remington, they were also working to develop another high performance round, albeit much larger than the little rimfire.

Julian Hatcher's Textbook of Pistols and Revolvers unveiled the new super round:

Without reading Major Wesson's mind, it's impossible to know why, exactly, the chambers were recessed on the new .357 Magnum. It's not like there was ever any balloon-head .357 Mag brass to worry about handloaders blowing up; the Magnum (there was only the one, at the time) was a thoroughly modern cartridge with a solid case head.

With the hype surrounding the cartridge, though, it would probably have appeared as a sensible precaution, at least to the buying public. In Hatcher's words,

"Smith & Wesson do not recommend this gun for the ordinary user, as they state that it is intended for men of large build and more than ordinarily powerful physique..."

...which seems almost quaint, looking back from the current era of AirLite Scandium Magnums and four-inch .500S&W X-frame revolvers.

The recessed chambers remained a hallmark of centerfire S&W revolvers in magnum chamberings up until the launch of the L-frame Model 586 & 686 in the Eighties, after which it went away, in a tacit admission that it was an entirely vestigial holdover.

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