Pa has the only flinter only season that I know of. Pistols for either the late flinter season for deer or the earlier "any muzzleloader" season must be at least 50 cal. Small game pistols must be muzzleloaders less than 40 caliber. but cap and ball revolvers are not muzzleloaders. For Groundhogs and Coyotes there are no caliber restrictions. I use my Ruger Old Army on groundhogs. I average maybe a dozen a year that way, although the number of groundhogs has dropped substantially since the eastern coyotes moved in. Seems the eastern coyote population exploded in the last ten years.
I recently picked up a 32 caliber flint pistol that I would like to try for small game. The wild pheasant population has completely disappeared here, since about 25 years ago. Quail are gone too. The rabbit numbers are way down. About the only thing we still have plenty of are tree rats. 40 years ago, a hunter could bag his limit in pheasants and rabbits with less than an hour in the field. I have seen two pheasants in the last six years, and I am sure they were escapees.