Why no body shoot machine guns at 45 degrees? [closed]

Absent of air resistance, arrows will fly furthest on horizontal plain at 45 degrees angle.

Why machine gunners do not use this tactic and shoot further?

Is this because bullets have more air velocity drags?

Should this be asked at military stackexchange?

• Generally, the goal of firing a gun is precision, not distance. If you fire a gun into the air, the bullet will become subject to dynamical atmospheric effects that will make it nearly impossible to hit a target. – Dmitry Brant Sep 28 '16 at 2:42
• we no longer have mass troops against mass troops? Oh better crowd control mechanism is available for splash damage like mortar. I see I see. Should be on history stackexchange. – user4951 Sep 28 '16 at 3:06
• I'm voting to close this question as off-topic because it is not about physics. – ACuriousMind Sep 28 '16 at 12:23

Leaving out the question of whether or not that's a worthy mission, just recall that the kinetic energy of a moving object is $\frac{1}{2}mv^2$, where $v$ is the object's velocity vector. Bullets, unlike artillery shells or missiles, do all of their damage through this equation.