so last fall due to this thread I loaded up some 77 gr tmk and gave them to a buddy to try, sounded like the perfect round for his kids who are getting into hunting, and are needing something light recoiling. We both have tikka 8 twist 223s. I tried varget, h 4895, and imr 8208 before settling on 8208 cause thats the only one i could bet 2800+ out of. I have since switched to tac with the same speeds and accuracy and its findable. I was never able to get better groups than a consistent 1 inch 5 shot group. Despite both our guns shooting much much better accuracy with a lot of other bullets, mostly 50-55 gr varmint bullets, never tried heavier. I have aftermarket mags which allow me to seat anywhere I please, everything was tried.
So all together they shot 6 deer with them and here is where it gets interesting. Low 2800s muzzle velocity.
All shot broadside behind shoulder at 90 yards and under. No big whitetail bucks, all does and spikes. 3 went down fast. 1 stumbled 50 yards and left a lot of blood. 2 ran 50 to 60 yards and left 0 blood . 0 of 6 bullets exited. Nothing really found under the hide or inside besides shrapnel. Big holes in first lung, a lot smaller hole in second. No bones hit besides ribs. bullets seemed very splashy, not alot of penetration at these closer ranges. Honestly a tough 55 gr sp from speer, sierra or hornady(they all make a tough sp 55gr 22 cal) does better penetration wise.