I have used the 30 cal 165 gr GMX effectively on antelope, mule deer, and many elk.
I have never been able to recover the bullets from any antelope or deer. They just punch right through the animal.
On elk I have experienced both total bullet pass through but more often find the bullet just underneath the hide on the opposite side. Mushroomed perfectly and retained 95% of the bullet weight.
The bullets perform well enough for me, however I kill most animals closer than 250 yards, with occasional pokes out to 350 yards. The only disadvantage/ detriment of the gmx is that at distances under 100-150 yards the bullets blow through every animal I've shot. This has resulted in some of the animals running off to be recovered sometimes as far as several hundred yards before they expire.
This can be mentally difficult to handle when you're not sure if you missed the animal or your shot was perfect. Then you're left with wondering if the animal is dead/wounded/ missed and all of the possibilities that result from those thoughts.
I can say however that I've learned with using GMX bullets that if you had a decent rest, gun was functioning properly, and the shot is within your range- then you hit the animal. It won't always show signs of the hit but more often than not the animal is hit.
Plus side is that there is usually little bloodshot meat, and I never find pieces of lead in my processed meat.
Because of these experiences I am currently evaluating different bullets. I want something that has a higher chance of dropping the animal in its tracks. Looking into berger vlds, nosler partitions, accubonds, accubonds long range, or barnes lrx.
