In MN one can take game up to the size of coyotes with an air gun. Big game requires a Centerfire ignition.
In other states, deer, pigs, and even bear have been taken. What few pictures or videos I've seen have been of animals topping out around 200# which isn't necessarily that small. These aren't the typical pneumatic or spring activated pallet rifle and easily cost as much as a standard rifle.
I have a spring operated RWS in .177"/900 fps and a Crosman pump up pneumatic in 22 caliber/650 fps. I've used both to dispatch animals as large as coyotes back when I trapped but on a free roaming creature I try to stay around rabbit/cat sized animals.
That is one of the brands of "hunting" grade air guns I am familiar with. Air Force I think it is, is another one.
Powerful air guns have been around for many centuries. Lewis and Clark had at least one on their journey with which they took a lot of game. On the military side, either the Austrian or the Hungarian Army had a couple of battalions armed with air guns as they were not affected by wet weather as were the wheel locks and flint locks of the time.
Air guns have a much longer and deeper history than most realize. It is almost surprising how far backward air guns slipped in this country but it will be interesting seeing how they advance in the future.
Lumpy wrote:What's the largest game that can be taken reliably with an airgun, and at what threshold should you move up to a .22?
Pigeon, squirrel and rabbit should all be fine out of a typical break action springer pushing lead pellets around 1k fps. I've taken raccoons with head shots at 25 yards with pointed lead hunting pellets though I prefer to use my 22 rimfire on critters that size.