For the past year, I have been using the 120gr Hornady GMX bullet in my Howa 6.5 Creedmoor. I load the bullet to just under 2800 fps and consistently get 1/2 moa groups.
Between me and clients using my rifle, this bullet has accounted for 73 game animals, including Black and blue wildebeest, blesbuck, eland, red hartebeest, springbok and warthog. These bullets penetrate well, even on the larger antelope and expand reliably out to more than 400 meters.
In the photo above the bullet on the left is an unfired 120gr GMX followed
(from left to right) by bullets recovered from: 1. Blue wildebeest shot at 75m, recovered weight of bullet 119.5gr. 2. Black wildebeest shot at 485m, recovered weight of bullet 119.5gr. 3. Black wildebeest shot at 350m, recovered weight of bullet 119.0gr. 4. Blue wildebeest shot at 300m, recovered weight of bullet 117.6gr. 5. Blesbuck shot at 375m, angling towards the shot, the bullet broke its shoulder and was recovered in the opposite hind leg, retained weight 107.6gr.
On animals, even the larger ones, the GMX normally exits, leaving a good blood trail on animals that do not drop in their tracks. This is one of my favorite hunting bullets in the 6.5mm cartridges.