I have a Crossman Quest in 22 cal. Scope came with it. I've killed many Ground Squirrels in the yard with it and a few closer to 45-50 yards. If hit, they are dead.
HOWEVER.... I must shoot from deep within the House out through a slightly opened window because it is very loud.
Coyotes have been hit by my Wife....she run's outside after them and cares nothing about noise or being seen. I believe most of her hits are GUT shots. One must have been a Heart shot because we saw it run from the back kitchen door area out into a field then flip in circles, dying right there.
If I hear the Chickens bauking, I use a CCI CB Short and lately, the newer CCI 22 Long's labeled as QUIET. I'm not interested in a flop dead shot. Its nicer to have them expire a few hundred yards out in a field.
Here is another "HOWEVER"... Look at
http://daystate.com/ I have used these and they are the very best. I have two Anschutz each costing into our +$1000.00's and they are very good but NOT as good for Hunting as many found on/in the above site. Deiter Anschutz, a Friend, gave my Son one of their Target Guns.
But our England folks sure have learned how to do the most with a pre-charged Pellet Rifle. I use a SCUBA Tank to fill ours and its all very safe and easy. Folks here in USA never really get to see "A REAL PELLET RIFLE" so I suspect some of you may be surprised after reading about various models. Spending such $ is a personal matter. Truth be known, if such Pellet Rifles were at our fingertips, we would be using it a lot and, Year Round. Plus, when showing a friend such a gun, many will want to borrow it.
Jagerdad