Its not about fps. It the energy that counts. Pellet weight and caliber are factors. A 30 gr .25 cal pellet going 450 fps( about 13ft/lbs) is far more likely to drop a squirrel than a 7.9gr .177 going 650fps (about 7 ft/lbs). To take something like a coyote you need lots of energy, at least 18 or 20 ft/lbs to even think about it, even then you need good shot placement. You most likely won't get close enough for an effective shot with a low power gun.
