Load em up with the R22 and go shoot em. If you have a clock and know what they're running, do it again at 40 degrees or lower and see if you have the same speed.
I've found R22 to be very temp sensitive, Good lock to ya
I use Re22 a lot. Sighting in at the same range of temps you will be hunting at, negates the temp swings. All powder is temp sensitive to a point. Some are less than others, however.
