In all the decades of hunting here's something I've never really concidered. When I sight in my rifle it is usuallyduring the summer butrifle deer season is not untill the end of Nov. to the end of 1st week in Dec. I've never had a difficulty putting one in the boiler maker at 300 yards with the ol'7mm mag so I've ner really considered it. Has any one experimented with this? Maybe with it still being -15 to 20 up here I might go out a punch some paper just to see if there is any real difference to when it gets warm.