Powder charge, winter vs summer nodes?

[DngBat7]

I don’t do much cold weather shooting. Last summer my accurate node was 40.5, about 80-85 degrees, probably humid. Yesterday it was 50 and cloudy. I noticed I was at 42.5gr can it really change by 2 grains due to temp? The only other change I made was from Hornady to lapua brass. Primer, powder and bullets are the same.

 

[MikeMcCasland]

The 2gr increase probably has more to do with the change in brass than it does a 30 degree swing in temperature. Changing brass will change your accuracy node every time; reason being is the internal capacity of the brass is different, and it will take a different amount of powder to get you into your node.

 

[K22]

I shoot and hunt all year around. Before dedicating rifles for summer vs. winter hunting I noticed changes in point of impact from the mid summer high 80's to the winter low 30's. This was particularly evident with ball powders such as H335 and H380 which I don't use anymore for other reasons. But even with stick powders I noticed about an 1/2 to 3/4" change in elevation. Probably some of it due to the differences in air density between hot and cold weather.

The way I dealt with it at the time was to adjust the scope setting rather than change the load. Even now with rifles dedicated for summer vs. winter hunting I check at the range at the start of the season to verify scope setting and repeat when the temperature changes radically, i.e. hunting ghogs in the early spring where temp is in the high 50's to low 60's to mid summer where it can be high 80's low 90's.