[harpseal]

I personally would want the 20mm Barret at minimum for a T-Rex that thing has way too big a set of teeth to trust anything less.

[Long Cut]

"I personally would want the 20mm Barret"

I'm assuming, for discussion's sake, that we are limited to non-destructive devices, AND that we would want to preserve as much of the meat as possible.

Believe it or not, in a discussion of this same topic in my shop, one guy SWORE that he could do it with his trusty bow and arrow. Lucky for him, he'd never had to prove it. He was a weird one, BTW.