Yeah, both Slade and Jinny have a bolt action rifle that fires .117. Which, according to my google-fu, should be enough to cleanly take down a rabbit or similarly sized animal, while also being one of the lowest caliber bullets. Only one smaller is .22LR which is only a small step up from BB pellets according to the same google-fu.

How true all that is I'm not 100% but does sound right from what I've learned from friends of mine who are more interested in owning guns.