We already have them shooting over 400fps and over 100fp of KE. So with no human limitation how far can they go?
you know KE is irrelevant in archery, right?
as for how far can they go? I'd bet you $ the top 20 crossbow shooters can't beat the top 20 compounders in a 3D tournament, so regardless of the listed speeds etc crossbows aint no more better in the woods than a compound
a .243 is an exceptionally good rounds, a .223 in the right hands as well - the magazine capacity thing is something I guess, no doubt an idiot would rattle off 30 rounds at a deer running across a field (I thought crossbow shooters were the slobs??)