Not nessi-celery. 17-4 was moving the gas ring from the yoke to the cylinder, in 1977. 1982 is when the pinned barrel was eliminated. Its the logic factor Sip, and as you know, logic was not a dept. at the factory. The elimination of the pinned barrel did not generate a new dash # in the models they had in production.
The recess has value in a .22 RF as the copper / brass shell has to be soft for the Rim fire priming to work and there is a possibility for rimfire cartridge to blow out the edge of the rim. The recess has been a safety function since the 1930s to protect the shooters to the side. Recessing .357 magnum and 44 Magnum and 41 Magnum chambers is not necessay as these cartridges were solid head way above the rim at least since WW2. Ir made a nice selling point but cost way more than the actual value.