A consideration. The Sheridan Blue streak and Silver streak .20 caliber rifles meet your specs. I have had one for about fifty years. I has killed beaucoup bunnies and squirrels, the odd woodchuck and crow. I've had a scope on it off and on. Finding pellets is not6 quite so easy, but it's not a problem. Like Windfall said above, the .22 CB loads are a very viable solution. I take one with me to my "deer stand" when I am crossbow hunting and it doesn't bother Bambi that I am popping varmints. They are quieter than the firing pin out of a long barrel target rifle. They can be an issue accuracy wise in some rifles because they are short but buying the CB longs helps.
