A few concerns:

 

?   I can see that you want the ultimate suppressive fire vehicle, but dual GAU-19 so you can lay down 4000rpm is definitely overkill.  One should be sufficient.

?   I am also concerned the weight and bulk of 10,000 rounds of .50cal ammo, in presumably 1000 round drums. 

?   I note that you have include "1 collapsible rail crane to load ammo canisters".  You are not clear as to whether it is to load the cannister on to the vehicle or into the mount.  How much does a 1000 round cannister weight?  What would be involved and how long would it take to swap out 2 empty cannister from the mount?

?   The SMAW rockets maximum elevation will be limited because the exhaust would impact and spread on the vehicle roof at high elevations endangering the crew and nearby troops.

?   Most AAA mounts are open top for a reason.  You will need a complicated articulating set of armor to permit high elevation fire without leaving opening that snipers can exploit, and it is unlikely that it can be made gas tight.  Most of it will be ballistic glass in your design, so flat pieces only.

?   Your commander/gunner is locked in an ballistic glass green house with a massive heat generating weapon, better add a powerful air conditioning system.

?   Add a full sensor system (light intensification, FLIR, etc.)

 

The SMAWs are a nice idea, but you end up with no anti-armour capacity beyond perhaps 400m. 

If you want high elevation, a remote turret would make more sense, coupled with distributed sensors fused into a composite image for the crew.

How will you support the infantry if you don't even have a coffee machine in the back of vehicle, eh?

My first thought was that it was intereting that you focused on AA guns, because toward the end of WWII the Germans built a light 30mm autmatic cannon called the MK 108 as an aircraft and antiaircraft gun. It fired a relatively low velocity cannon rouund at a muzzle energy that allowed it to use simple blowback operation. Today the descendent of that weapon is a ubiquitous presence in the American armed forces--the Mk 19 autmatic grenade launcher. Dismounted infantry support, HUMMVEEs, Stryker armored cars, and mounted on trucks, howizers, FASVs, etc., this weapons does it all.

 

Another thought is that if the most dangerous fire support weapon is basically a copy of the ZSU-23-4, the enemy is eventually going to stop shooting RPGs at it and start packing .50 sniper rifles and perforating it that way.

 

So, the question is, which do you primarily plan to operate with? Bradleys & M1s or Strykers? 

 

If you are operating with Strykers it should be based on the Stryker chassis. The M113 isn't going to keep up well with strykers on roads, even with a bigger engine, since there is so much extra stuff loaded on.

 

If you are going to operate with Bradleys and M1s base it on either an M1 or Bradley chassis, because the M113 chassis isn't going to be able to pack enough armor for the threat environment that those vehicles operate in.

 

Instead of a jack of all trades master one--or better yet make a version for each role.

 

Gatling guns are nice but there are better options. If you are supporting infantry I'd suggest thinking about what actually kills infantry. That's artillery. Tanks and other infantry just finish the job. Without effective artillery support your enemy's tanks and infantry will break themselves against your defenses. Defense is and always has been the stronger form of combat. The only way to change that is for your enemy to use the immobility that comes with an entrenched position to array massive offensive artillery firepower against you.

 

As such, I'd say base your weapon on the Millenium Gun. It has plenty of firepower and can also destroy incomming rounds. I'd say equip each vehicle with essentially a firefinder radar that calculates the aproximate impact point of the incomming rounds and compares that impact point with your blue force tracker map, then only attacks those incomming rounds that will hit near the units it is responsible for defending. Once the enemy attempts to move into an attack mode, then you can still use the autocannon against the enemy infantry and any light vehicles supporting the assault. One major weakness of a .50 cal weapon is that it cannot fire explosive ordinance. Hence it would also be unable to effectively engage advancing enemy infantry in dead space. An automatic cannon firing airbursting rounds would be very effective in this capacity.

The 30mm chainguns with explosive projectiles and a smart fuse with variable settings may be superior to the .50cal for 2 other reasons:

 

?   Explosive shells are much better than solid slugs for creating a breach if they detonate within the wall being breached.

 

?   Limiting penetration/overkill.  This is a big problem in builtup areas, and the .50cal has a bit of a problem here.  I have seen a number of articles (mostly in Armor magazine) where it has been noted that when you fire a building with a .50cal it is capable of easily penetrating 6 to 10 walls and causing unintended casualties.  This was seen as such a problem that some felt 120mm HEAT rounds were preferable in many situations to limit civilian casualties.  The shrapnel from a round that explodes after penetrating a wall generally will not penetrate more than 1 more wall.

a combo of MK-19 and M2 seems to work just fine on the M-1117

 

Sincerely,

 

Keith