Airguns don't have a lot of power, and so head shots are normal--even for quarry like small birds at 40-50 yds, and especially for "larger" live targets like groundhogs. And the animals are not always "immobilized" instantly--sometimes they are just wounded enough for you to walk up and put another finishing shot or two in them.
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-I don't know of any $200 .25 air rifles. The whole "Career" family was priced up around $350-$400 last time I browsed. There's at least three companies making very similar CO2 (-and often lever-action) guns--"Career", "Eun Jin" and "Sumatra", and there are US companies selling them. I don't got none; they look ugly but seem to work well. They range 30-80 ft-lbs of power, most have an exposed knob for some limited power adjustability.
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