Odly enough I haven't seen any splash damage in my tests...
The logical ammo allocation is 48 divide by 4 slots =12
and then (weapon slot) 12 divided by (number of tubes) 4 = 3 as you correctly stated.
But the point is that I find that the rockets should be more powerful (at least shooting at an NVA platoon [not pinned on clear terrain] from a distance of 3-4 hexes should make 1 kill, so since we use the stock US OOB, then a way to magnify (4x) the efficiency of the FFARs is by assuming that each salvo of an 4x 2.75in FFAR is only one Tube (instead of 4)
Re: ARA 2nd Bn 20th Artillery 1st CAV Div
Threaded Mode