this was my grandfather's "primary deer-getter" ( his words) that I inherited 4 years ago upon his death. A 1971 vintage Weatherby Vanguard with the Leupold 3x9 Vari-X 2 that he bought new. He used just plain jane Remington core-locks for as long as I can remember, and I inherited 2 and a half boxes of those. I got a box of Hornady "Light Magnum" .243 in a 100 grain load, just to play with. They shoot just a tad tighter ( .779" best group for 3 shot groups) than the Core-Locks, but then the last group I shot of those was .845, so SHOOT! I measured them outside to outside, then subtract the bullet size, right?
Took this buck at 127 yards (measured with a Bushnell range finder) and they worked just fine, or so the buck acted like!
Ken B