Has anyone noticed that retumbo is sensitive to cold vs warm weather? I got my pet load out for my rifle which is a 30-378 which I shoot 210 vlds over 103gr of retumbo. Usually, in the summer, is about a 1/2" group at 100. If you go to hodgdon website it says 101-107 for 220s (they dont have anything for 210)I have had the gun for 2 years but never shot it when it was cold. So today, I went to shoot my pet load for a winter elk hunt and I had to beat the bolt open with a hammer. Anyone else notice if retumbo is heat sensitive?