We are talking about sighting in the mini-14 right? So I ran my Infinity program on a 55 gr SPT at 3200 fps. at 80 degrees, bullet drop at 100 yds is 1/100" less than at 30 degrees, at 300 yds it is about 1/2" less than at 30 degrees. Ok boys, and girls how come a bullet drops less at higher temp?...because the air is less dense when hot, and to some degree near the ground the heated air gives the bullet lift. Air is less dense when humidity is low, Air is less dense when altitude is higher (also bullets, and golf balls drop less because gravity is weaker at high altitudes), if we have less air friction, bullet and golf balls retain more speed. I read somewhere if a 22 LR were fired in a vacuum at sea level, it would travel 12 miles, a centerfire much further....sorry guys, I got carried away.
So go ahead and sight it in. For hunting you won't notice the diff, unless you are shooting 500 yds are more.