Hey Robert!
I really appreciate your mod for Arma 3, my man. Your weapons packs for Arma 2 were top-notch and I know they'll assume the same standard in Arma 3. However, I'd like to put in some real constructive criticism coming from someone who shoots guns in r3al l1fe.
While the opinion that "real" recoil does not literally kick the muzzle upwards is true, it's also false to a certain degree. When shooting a high-powered rifle like the M16 from a standing or kneeling position, the torso, more specifically the trunk, will have nothing else to do except lean backwards, resulting in the illusion that the muzzle kicks upwards. More importantly, instead of focusing on the upward recoil, we should highlight that these rifle rounds will cause the weapon to shake - it'll literally shake the rifle in your hands to the left, to the right, diagonally, backwards, and forwards and all the different directions you can think of - all at the same time. With a rifle like the M16, as powerful as it is, this "shake" is definitely noticeable, but not exactly detrimental to rapid shooting at point targets within 50 yards.
I'm not sure if you have the power to modify the entire "recoil system" of Arma 3, but I just wanted you to know this stuff. Maybe you already knew it, but it's just really important to someone like me because I genuinely care about the precious time and effort you put into your projects. Thank you, Robert, for serving the Arma community so selflessly over the past years.
-nextdayair8