Hello martin may, and welcome to this forum,
Even though it began as a Military cartridge, (well over a hundred years ago?) it has by reputation, become one of the best hunting cartridges on earth for things like deer, black bear, wild boar and quite a few African species (within reason).
Low recoil and the fact that most rifles made for it have been accurate, plus with 140 gr bullets, it shoots plenty flat enough for longer shots if needed.
Many of today's 6.5 bullets are generally of higher quality (tougher) than yesterday's bullets were and so, not as much meat is lost to shattered bullets today / penetration is better than it used to be, generally speaking.
All these things make it a very good choice.
My wife is a Lawyer and so, I almost never share my pet hand loads with people but, my 20" barreled CZ Model 550 full stock carbine is very accurate with 160 grain Hornady RNSP at about 2300 fps.
So far, I have not hunted animals with it yet, but it does kill paper targets and aluminum cans impressively.
Cheers,
Velo Dog.