I've noticed something extremely unrealistic about the ammo type cycling- changing ammo types doesn't require rechambering! It's as if the round is undetermined until the moment of firing, and instantaneously changes types on command (something even modern rounds have trouble doing).
My wish is that to change rounds the choice needs to be made and then confirmed via the fire button (default, but remappable- firing does not confirm, pressing the button the confirmation key is mapped to does). Once the choice is confirmed, the reload delay occurs and the reload sound plays. Once it is done, the new round can be fired.
When switching rounds, the color of the round text would turn neon yellow instead of the usual color to indicate that it is the selected round, but not the loaded round. After confirming the choice via the fire button, the text returns to its usual color.
If the selected round matches the loaded round and the fire button is pressed, then a click (like the sound of a hammer falling on an empty chamber) will be heard, and then the round text color will return to normal. The round will not fire in this case, but an additional click will fire the round.
This wish will enhance realism, and provides a simple, effective means of changing ammo types without leaving the WASD and mouse or HOTAS setup.
-Penguin