AIRGUN FPS

This would be VERY quarry and shot placement specific. For squirrels, cats, and dogs airsoft guns work very well. with any kind of bird even an airsoft gun can be fatal. Most small birds have very thin skin and if you happen to get between the feathers (which is easy if you are shooting against the grain of the feathers) serious damage is often the result.

I'd lean more toward airsoft (as mentioned) or paintball if I wanted to sting rather than injure them.

IMHO, you probably need to rethink your objective. 

Any BB or pellet gun shooting slow enough to not cause injury won't be accurate enough to place the shot correctly. And most importantly, even a BB at 250fps can cause injury or be fatal if it hits an unprotected part of the animal's body.

R

 No pellet or BB rig will work. Airsoft, traps,pepper spray,. Even a red ryder is too much.

John

I vote BLOW GUN lol stun darts gets them every tiem

Maybe enter this on Google, and go from there ?
cage for trapping squirrels

Sorry to say and be a little rude.. ....just blast them. End of them and story.

LOL! Lins you crack me up! But ya that's what most people do.

Airsoft would definitely do it! Just avoid their eyes and it will leave a tiny bruise but not penetrate their skin.

I took a different approach for pests I wanted gone, but not 'gone'. What I did was I got a slingshot and some paintballs. I don't aim at the pest, but near it. That way when the paintball bursts they only get a bit of spray on them and know something doesn't want them there.

If you pest is dog or cat it'll learn. If its a squirrel, house sparrow, starlings, raccoon or opossum you're better off just getting rid of it permanently before they really begin to cause problems.

I find this perplexing at the least and almost unethical.Use some noise or turn the hose on them.Trying to "sting " them is like your neighbor throwing a rock at you to move you along.It can end badly,with scaring the pest being the most unlikely outcome.Injury being more likely.

I'll stand behind the air soft suggestions.

I'll also assume that the "pest" is a neighbors beloved poodle that's leaving presents under the tree every morning.

I got a little pistol that came free in a package of pellets and it's hilariously accurate for $20 and a ton of fun to shoot.

I can very reliably hit a pop can at 10 yards.

I have a fully automatic one that shoots a lot better and would make a pretty terrifying suggestion for the intruder to permanently exit the premises.

Be cautious of the cheaper clear plastic airsoft, their accuracy is not very good in my experience. If you shoot PB pistols you could get a replica, that would provide you some backyard practice.

Almost any airsoft with a battery will work just fine at 30 feet, look close as some have a "hop up" which is a small adjustable piece of rubber in the barrel (essentially puts back spin on the pellet allowing it to travel further and straighter).

Forget an airgun, just post this pic throughout your yard and the pests will be frightened away.

@HauntedMyst, thanks for posting....now I cannot sleep!&$%#$@

I dont know about where you live but here in Canada it would be an offence under law to willfully harm without the intention to harvest that squirrel ...just food for thought if there bothering you that much dispatch them humanely via gun or trap ...or I would say leave them alone 
just my 2 cents Jonathan