Interesting comms

The same way it affects an aircraft!
Not entirely. The bullet is fired from a cartridge with pre-packaged fuel and oxidizer (the gunpowder). Altitude has no effect until the bullet leaves the barrel, at which point it has less wind resistance to slow it. The airplane also faces less wind resistance with altitude, but will--even with a turbo--struggle to maintain power if the altitude is sufficiently high.
The same way it affects an aircraft!
Lol. Ok youse engineers, get out your slide rules. How does altimeter effect the velocity of a bullet.:idea:
An altimeter is a measurement device and would do nothing to a bullet unless the bullet actually hit the altimeter.

And yes, I am an engineer.