I’m actually going to go with TexasPatriot308.
Too many 6.5 shooters are imagining themselves long range snipers, thinking a hit equals a kill. It may in combat, but not hunting.
Most HUNTERS using the 6.5’s due to rag-writers ballyhooing the high sectional density bullets, and long range target accuracy are using either 140gr heavy game bullets or match type bullets that either don’t expand, or blow up, fragmenting.
Unless a bone is hit or heart hit at top through major vessels, an animal can make a lengthy run. I’ve seen it with my own use. I much prefer the 100-125gr 6.5 bullets to the 129-160gr bullets for 80-200lb deer.
I’m not just picking on the 6.5, but the .243, .30/06, .338, and .375’s have exhibited similar characteristics. I’ve seen deer hit with either a 175gr Corlokt from a 7mmMag or 220gr from a .30/06; either badly torn up, or a mid section puncture wound running miles...
Just right bullet placement or a better balanced bullet expansion, weight retention is the key. I prefer to heart-lung or CNS hit my deer/pigs as I eat them. So, I prefer something like a light to mid weight Ballistic Tip, or Corlokt to a heavy tough bullet. Also, keep ranges reasonable. Under 400yds. Adequate impact velocity is essential to killing performance. And, shot placement X3.
Added, year before last, I was hunting a shotgun only area. I hit a smallish 8pt buck at 110yds with a Federal 5/8oz Sabot slug. Deer was knocked down and got up and ran out of sight. I tracked it for ~400yds till I ran out of blood trail. I returned 4days later to see 20 vultures working the carcass on exposed lakebed. I later returned to carcass for post mortum exam. Two ribs midway back (3”) were broken from obvious bullet impact.. the .54cal slug penetrated the deer like it was toilet paper. Deer ran a 800yd zig-zagging arc.
In open terrain, it would have been a easy retrieval. In dense, wet S.E. it was a loss.
So, even a small, tack driving cannon, can lose a deer!