I have a question about the details of calculating bullet drop at longer ranges.
I will preface my question my sharing an experience I had last month hunting elk. I shot an elk in the dark timber at 590 yards. The shot was at approximately 7500 feet elevation, 10 degree down hill shot, temperature was approximately 45 degrees F, and my Leika rangefinder said it was approximately 23.0 mm Hg. I was shooting factory 225 ELD-M out of my 300 PRC in Christianson Ridgeline at 2830 FPS. I doped my scope 10.25 MOA, put the crosshairs on the mid crease and let her fly. The animal was quartered away facing right standing on a steep hill so the head was up and away. He was looking back over his left shoulder so his head was almost directly above his shoulder. When I pulled the trigger I heard the distinct "smack" and the animal dropped in his tracks. Upon retrieving him the bullet struck the base of skull which had to have been nearly a foot high. I felt like I was more lucky than good that day.
My question is this: if I use the atmospheric pressure from a kestrel, or advanced rangefinder, is that the only piece of information needed to account for temperature, elevation, and humidity? In other words, does anyone know if the "black box" is imputing temperature, humidity and elevation to calculate the pressure, or are all days points needed to accurately predict bullet drop? Equations or references would be more helpful than opinion here as I am sure the answer is known. Any physics or chemistry majors out there?
I will preface my question my sharing an experience I had last month hunting elk. I shot an elk in the dark timber at 590 yards. The shot was at approximately 7500 feet elevation, 10 degree down hill shot, temperature was approximately 45 degrees F, and my Leika rangefinder said it was approximately 23.0 mm Hg. I was shooting factory 225 ELD-M out of my 300 PRC in Christianson Ridgeline at 2830 FPS. I doped my scope 10.25 MOA, put the crosshairs on the mid crease and let her fly. The animal was quartered away facing right standing on a steep hill so the head was up and away. He was looking back over his left shoulder so his head was almost directly above his shoulder. When I pulled the trigger I heard the distinct "smack" and the animal dropped in his tracks. Upon retrieving him the bullet struck the base of skull which had to have been nearly a foot high. I felt like I was more lucky than good that day.
My question is this: if I use the atmospheric pressure from a kestrel, or advanced rangefinder, is that the only piece of information needed to account for temperature, elevation, and humidity? In other words, does anyone know if the "black box" is imputing temperature, humidity and elevation to calculate the pressure, or are all days points needed to accurately predict bullet drop? Equations or references would be more helpful than opinion here as I am sure the answer is known. Any physics or chemistry majors out there?