I do not shoot BenchRest, however, I do shoot F-Open at 500, 600 and 1000. It has been MY experience that you CAN load develop at say 1000 and obtain excellent groups. That being said, IF the E.S.'s are not tight, you MAY not have a good load at say 600 yards. Although L-O-W E.S.s are not always indicative of excellent groups at a given range, it can be indicative of accuracy across all ranges.. I have found, however, that if e.s.s are NOT tight it is not always possible to have excellent accuracy across all distances. Conversely, if you are shooting excellent groups at 1000 AND have tight e.s.s, you WILL get excellent accuracy all the way in to 300 yards! Not always so in the reverse!