Discovered this one recently, and thanks to Groove's explanation, I was able to make sense of what had happened. Here's a video showing just how crazy it can get:
https://youtu.be/dUH1DeIYMMw

The indirectHit aspect of this is one of the most significant changes that could be done to Arma's damage modeling. The way it works, as described, is an archaic system that has been in desperate need of replacement for many years.

My own thoughts and suggestions on how this could be addressed can be found here, in text and video form:
http://dslyecxi.com/arma-3-fixing-the-action-menu/

We ran into this in our most recent session, and yeah, it's really... not good. Those sounds need a reworking.

Excellent report.

My own thoughts and suggestions on how this could be addressed can be found here, in text and video form:
http://dslyecxi.com/arma-3-fixing-the-action-menu/

This thread claims to have a solution:
http://forums.bistudio.com/showthread.php?160029-Headless-client-battleye

However, even when not using BattlEye, this is still an issue. Turning on BattlEye and making the suggested changes does not resolve it.

Seems to be an issue in .75.108378