I don't believe I've ever tried to do something like that at a low level.

I generally wait to fight giants until I feel like I'm strong enough for it. 20's-30's?
(Honestly, I'm having a hard time thinking of times I did that at all. I suppose I may have gotten a "go kill the Giant" quest to a camp that also had two mammoth, but it's not common. Or at least I don't recall it as such. Hmm.)