I've never hunted medium/big game with an air gun; nor owned one that would be suitable. For the purpose of discussion, I just did a brief search of Alabama laws regarding hunting with air guns and it appears that there is a .30 caliber minimum for Deer, Boar (AKA Hogs) and Coyote; apparently Turkey may not be hunted with air guns or single projectiles - it specifically states no shotgun slugs. As far as I researched, there are few other interesting stipulations such as air soft is legal for some smaller species and frogs may only be hunted with air guns of .25 caliber or less - they are probably concerned about ricochet due to the proximity of water rather than, "Wouldn't be sporting to use that .45 on amphibians old chap." Although, .30 may be on the light side, in my simple, humble opinion, .35 will definitely cleanly harvest a Deer - under the right conditions, of course. Why wouldn't a "space age" Benjamin in .35 and a hand pump work for someone on a budget? Oh, thanks for putting up with the new guy...