i know there must be dozens of variables, but nary a load, in any grain weight, rivals that of published reloading books???? my cheapo 130$ chrony mirrors a friends high end readings, so i checked my chrono. Any powder/grain/primer etc combo. i try is 60-180 fps slower than what nosler/hornday reloading books publish for the same grain load. Velocities are slower regardless of ambient temps, although not as slow the wamer it is.. is this commom?