I can understand the problem with lung shot animals moving off a ways from a solid lung hit...the lungs are the gas line and it takes a few seconds for the gas (blood) to run out before the engine is out of fuel.
By force of habit I have always try to angle shots into shoulders coming or going and catch the vital plumbing along the way if I can...this immobilizes and destroys vitals at the same time,and tends to work well,whether it's a pronghorn or brown bear,but nothing is guaranteed once you cut loose.Your bullet has to work.
One 6x6 quartering "on" was hit on the point of the shoulder with a 180 NPT at not far off 500 yards and collapsed like the proverbial dynamited smokestack.The bullet broke through the heavy bone, wrecked the chest and was recovered against the hide on the back ribs. He never got up.
But another hit near the back of the lungs at about the same distance sauntered off 75-100 yards;bedded down and jumped up as I approached and had to be finished at that point.Conversely a 300 pound bear ( one of those little Maine bears
was hit through the lungs with a 140 Bitterroot was DRT and never got up...lungs were a train wreck.
My last mule deer buck was on the move and hit through shoulders and spine with a 130 Partition that went through and through at about 80 yards. He was dead so instantly that I saw his head snap between his legs as the rifle recoiled.
Another had his lungs scrambled with a 130 Sierra but had enough fuel left that he clung to life but did not go far.
I have not had much problem with ruined meat but tend to use tough, antiquated designs like NPT's and Bitterroots; but give them lots of velocity and twist...they tend to kill like bombs out to 400-500 yards,as far as I have used them,and penetrate more than needed regardless what I hit,which is why I keep using them.Putting them on bone helps expedite matters,too.
