I shoot a similar load, 130gr of pellets and the 300SST. It averages about 1945fps and yes it is higher at 100 when 2" high at 50 by about 4" from center. Depending on your setup 6" is not unreasonable. If your sighted in at 100 you should only be about .5 to 1 inch high at 50. Good luck with it and keep us informed.