"A commonly accepted threshold for the*minimum*amount of kinetic*energy needed to kill an elk is 1500 ft-lbs. For whitetail*deer, the*minimum*amount of kinetic*energy*is 1000 ft-lbs."
COMMENTS:
The above is talking about using high velocity rifle hunting in the West, and at longer ranges. And it REALLY is talking about a MINIMUM number. So, MORE is better. The above doesnt even consider the 'shock' factor where it is MUCH better to be HIGHER also(as in bullet performance).
If deviating from above, such as at lower handgun velocity, personal experience is... I prefer heavy bullets that are capable of going through both shoulders of a deer, that would also allow a high probability of a quick kill, one way or another(as in quick approach to safely dispatch). I just DONT see that 'reliably' happening in rugged country or near an adjoining ranch/property, using under a 300g projectile. Just wanna avoid a long tracking ordeal, for many reasons.
On elk, have shot 2 bulls that went well over 100yards in heavy cover, with a double lung/heart shot, using 375 & 416 with reliable jackets, these arent ultra high velocity calibers, even at max, BTW.
Another younger bull anchored with 375 shoulder shot, it took all of 5 minutes to finish while it took me 10 minutes to get there. Have also seen a buddy's 30'06 round explode inside of an immediately dropped elk shot at 100yards, but have seen a number of elk lost too, with 308 caliber. Have seen more WT deer lost as well, with .243 heart/lung shots in 1980s.
So, to me... only 'highly' experienced handgun hunting on big game - and should be capable to deliver at least as well as a big caliber muzzle loading rifle (& its accuracy), plus with needed broadside shooting/hunting skills. Range such as 100 yards max (or so) depending on shooter, shooting REST, hunter and of course proper gun, bullet-weight & sights. Under 60 yards is much better, JMO.
With scoped 475 in 400g, perfect conditions and I mean PERFECT, In past, I would not have shot beyond 140 yards at deer, 70 yards at elk(and for Bull, I'll stick with rifle). I dont archery hunt anything bigger than deer, and have missed every time. Chagrin.
I say 45acp is out, unless surviving or a very rare setup.