Is this thread about the 10-shot revolver or about hoarding .22 ammunition? I have a perspective to offer on 10-shot revolvers and thought this thread might be the place.
I have owned 2 10-shot revolvers, both S&W. I'm going to make the case that revolvers are properly designed with 6 chambers in a normal sized cylinder, and perhaps 5 chambers in a small cylinder such as the SP-101. The argument is based on the fact that with 10 shots, 3 chambers of the 10 will be within the gas blowback area of the forcing cone.
The chamber being fired obviously should be lined up with the barrel, but the 2 adjacent chambers overlap part of the forcing cone area to the extent that pressurized hot gasses are blown into the adjacent chambers during firing. The 2 adjacent chambers contain brass that is not sealing the chamber like the round being fired. The gasses will enter those chambers and some of the gas will find its way out the rear of the cylinder. This effect is most noticeable on the chamber at 11 o'clock, since there is only a spent brass case with no bullet.
I have confirmed (after consistently being hit with debris - not lead - on the left side of my face) that more gasses exit the left side of the gun. Simply place a white cloth over the gun, fire a few rounds and examine the cloth. There is more to the reasoning along this line. High pressure high velocity hot gas produces a vortex like effect as it enters and exits a chamber (or any nearby tube) the same as an intake manifold on an engine. Gas begins to swirl inside the spent brass case, effectively scouring out the firing residue left inside the case and throwing it sideways out the left side of the gun.
Beyond the 10 round effect above, there is more trouble caused by the same vortex effect. Many Smiths and perhaps Rugers also are drilled and tapped for scopes. Sometimes a scope mounting hole finds itself positioned just behind the forcing cone. The holes are usually plugged with set screws, but often the screws do not fill the tapped hole completely. If not, the high pressure gasses enter the threaded portion of the scope mounting hole and another vortex is created as the gas and lead vapor follow the threads in the remaining portion of the hole. Hot swirling gasses are reflected out of the hole and rearwards (among other places), where they strike the outside of the cylinder at the 12 o'clock position - burning it and depositing lead residue. On a blued gun the gasses can burn up the bluing on the cylinder at these spots in no time if the scope hole is left un-plugged.
There you go, my take on a 10-round cylinder. Some may find them attractive, but there are good reasons to consider sticking with 6 rounds in your revolver.
Carry_Up