Just for grins I tried my 155 Scenars pushed by 45gn of Varget in a comparison of cold (sat out all night at 5*) and warm (~65*). No difference, all right around 2900. Hard to beat that for a hunting load.
Was the gun cold too?
Yes, sat out all night. Two cold shots were 2906, 2896. Two warm shots were 2901, 2901.
