This again, and again, and again. ^
Why my reach for rifles are .177. When I do use a .22 then its farmyard ranges only, and in truth closer than that. If you are well familiar with any calibre and can hit perfectly then it really doesn't matter what calibre.
All that matters with 12ft/lbs air rifles is pellet placement. Heck, 10ft/lbs rifles will be as lethal to normal effective hunting ranges. Your effective range is to hit a polo mint sized target in all positions and conditions on the day. Normal critters just aren't big, nor tough, though vitals to hit are tiny.