I am headed out tommarrow to do some load development. While I am there, I was going to chrony some loads with US869. It has been about -8 degrees here and thought that would be perfect to keep some loaded ammo out side over night and some in the house at 68 degrees, chrony them and note the differance. I will post agian tommarrow after this test. I will be testing this in a 300 RUM with 180 ACCUBONDS. Has anybody tried this already and if so, what did you conclude?