Re: Reloader 17 temp v velocity change
Based on my experience (about 5000rnds of RK17 with 208 A-max, 190smk, and 190 VLDs in a .308 win F-T/R match rifle) RL17 is awesome for velocity, but like all PTSD double base powders, velocity swings with temperature... I'd you want to test it, put your rifle and ammo in the fridge, then shoot it over a chrono, that will give you an idea of velocity swings. I cannot speak for the 6.5x284.
Another option would be to bring some ammo loaded at your current charge weight "X" and some at X+0.2gr or so. That should make up for most of the temp variation, a touch more powder will definitely bring you back closer to the node than just shooting the same load in potentially 55degrees lower temp.
"Out of range" is a theoretical concept as far as I'm concerned. Send it!