Benchmark is THE powder in my 22-250. I tested most of the powders used in loading for this cartridge, and Benchmark was best, followed closely by Varget.
32.6 grains of Benchmark using 55 grain Sierra HPBT's with Federal 210M primers produced 1/4" groups at 100 yards for three shots. Varget was close with 3/8" groups with the same bullets and primers.
Bullets were seated .010 off the lands, and case necks were outside neck turned. Loads were assembled with Wilson seaters. I used a 36x scope for developing the loads, with a Hart Front Rest and a Bald Eagle rear bag.
Martyn