I shot 100gr corelokts for years with great success. About 15 years ago Remington changed something and I could never get good groups and gave up. I switched to 100gr blue box federals, they worked but was never satisfied with how quickly they put the deer down. Switched to federals with 85gr tsx. Solid copper core bullet. My first experience with a solid core bullet. I have been very pleased so far. Great performing bullet. The reason for changing to the tsx was it was the only bullet I found that would give consistent groups out of any of my 243’s I shoot. I could use 1 load between 3 different 243’s. All that said. Bullet placement is everything. Doesn’t matter what you shoot if you can’t hit what you are aiming at.