.243 Threads Are Special
And somewhat redundant.
Over several decades, I had the opportunity to shoot deer and antelope with a .243, and went through a series of bullets from 85gr-105gr. I never lost a single critter with 85gr bullets or 100gr bullets, and I can't say that one weight is any better, or different, performance wise, than the other.
The 85gr Sierra BTHP, 85gr Speer BTSP, and 85gr Nosler Partition all worked. My experience is that the DRT kills are not common, in fact I don't recall any that were not a bit high, that had clipped the spine. I never intentionally aimed for a shoulder, so I never recovered a single bullet of either weight. One season, back when WY had more deer and antelope, I was able to get a buck and doe tag for mule deer and antelope, and brought hope a set of each using a .243 with the 85gr Sierra BTHP. That same year, when I returned home, I shot a medium size whitetail in both PA and NY. The Sierra that held up well on mule deer and antelope at 150yds to 350yds, disappeared on whitetails at 35yds to 50yds. Neither bullet on the close shots left anything I could find when I skinned the deer and processed the meat. But the deer were dead in sight, so I'm not complaining. It might not be the best elk or bear bullet.
Whatever bullet you pick, the .243 is not going to turn into a 7-08 or .30-30 for punch and effectiveness, it will never be a .270 or .30-06. The .243 is for the shooter that can pass on a bad angle, and go home empty hqnded. The shooter that can place their shots with precision, and knows where to aim. The .243 gets it's magic from skill, not HP.