The Best That Never Was 2 (Prototypes)

[StainlessSteelCynic]

The key word here is almost, most are too troublesome to bother with due to the lack of gas sealing but there are some designs that are more suited to the task.
The Nagant M1895 revolver used gas sealing as part of its normal operation. This allowed it to be suppressed at around the same noise level as any supressed semi-auto pistol.

The point being, that supressing a revolver can be done. And with the idea being to produce a rapid, single shot, supressed weapon that retains the cases, putting a metal cage over the ejection port of a semi-auto would likely cause a distinctive noise as the shell hit the cage. There's also the problem of just how big do you make the cage to allow it to effectively capture all the cases without filling up to the point of jamming the action and how unwieldy does that make the weapon?