Heat here in Arizona and ball powders
I load all ball powders, except several rifles that don't like it.
Here in Arizona where it can get to 120 and in a vehicle up to 190 degrees!
I load in the winter, to day its 82 degrees, and when I shoot in the summer High Power Matches CMP i don't see a lot of difference out of an M14. When I was shooting off a cement bench I would see more of a difference in groups would open up a little.
My friend said he saw more pressure signs but nothing to blow his gun up.
Hope this helps?
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