Thread: Effects of cartridge temp on velocity

Originally Posted by Shearer

Yeah. That's what I am thinking. As the altitude increases the pressure decreases (because of reducing air density) but the temperature also decreases (increasing air density) but not necessarily at the same rate.
Please let a scientist clarify this before I talk myself into a hole.
In the example given, air will cool between 1.5 and 3 degrees /1000' of altitude, so a rise of 4000" altitude will equate to a temperature drop of between 6 and 12 degrees Celsius.

The main thing, I think, is that the lower temperature reduces MV. This largely offsets the lower pressure/air density so the trajectory is much the same.