Concept - Weapons Range

Each square may need to be 50m, rather than 100m as two ships moving towards each other would close range very fast.
Range is split into good and bad (ranged).

Ironsight
Ironsight accuracy is hard at 350. Anything beyond 400m especially 600m is unacceptable unless there is a large area targets or #binoculars are employed as adjusted fire. (IE It maybe all units have unlimited ammo but firing at unacceptable ranges is considered wastage also it will reveal you more to the enemy.)

4x Scope
Basic scopes increase outter accuracy an extra 100m (to 500m) although the limitations of the rifle remain.

10x Scope
Sniper Scope. May increase total range. Sniper scope greatly improves long range targeting but under 300m the FOV is too narrow to be as effective.

Sniper
What I would more commonly see as a sniper is actually seconday to the Heavy sniper.

7.62mm Marksman/Sniper, (800m~2500m)
You defiantely need a spotter for anything beyond 800m. Adding a 10x scope to a battlerifle makes it a Marksman. IE better accuracy but weapon is still limited.

12.7mm Heavy Sniper, (1800m-2500m)
Designed as both Anti-Light Armour and counter-sniper, the 12mm is the true sniper. However it is heavy, needs to be fired in prone and has limited rate of fire. So its more a support/mortar type role than front line unit. Definately needs spotter to calcuate firing solution.