As I know ammo for 14,5 mm machine gun or 30 mm gun is inside turret and have more or less the same space for ammo for the main gun.
I would think 500 rounds of 14.5mm ammo would take up less space than 500 rounds of 30mm ammo. Especially as the 14.5mm ammo would now be in a single continuous belt while the 30mm ammo will be in two separate belts for AP and HE.
I have three 25mm rounds from a LAV III in a belt and I have a 50 cal browning machine gun round that easily fits inside the empty 25mm shell case. The 30 x 165mm round is significantly bigger than the 25mm round, so while the 14.5mm round is also bigger than the 50 cal browning I am pretty sure that the 14.5mm ammo will take up less space internally than the 30mm ammo.
I suspect it would also be significantly lighter in terms of ammo weight and weapon weight.
As I know, turret from BTR-82A doesn't have space for any missiles, so spare missiles will be places outside turret somewhere inside vehicle. Different gun in that case in my opinion doesn't have any influence on missiles placed on turret. Maybe only with FCS, which maybe will need more space for operating additional armament.
Was thinking about 2-4 missiles on either side of the turret much like on the Phoenix or Strelets. Individual missiles are long and slim and could be stored in the hull behind the turret where the troops would normally sit in the troop carrying version.
Should be able to stack at least one full reload.
Talking about gun, I personally more prefer 30 mm gun, because it have longer effective range than 14,5 mm and is more effective against helicopters, specially armored ones.
I agree, but for the extra weight and size I don't think it is worth it. Most of the BMD-4s should have high elevation 30mm cannons already so for such threats they should be able to deal with them themselves.
My thinking is that the 14.5mm gun is a definite threat to most helos and light vehicles while not weighing too much or taking up too much room.
With the 14.5mm gun and 30mm grenade launcher and PKT MG I think the vehicle is well armed while reloading SAM missiles.
I don't want a vulnerable target, but I don't want to over burden it with the same weapons most of the vehicles it operates with will be carrying.
Its primary role will be shooting down aircraft but preferably at extended ranges... if a Helo gets within 30mm cannon range then there is something wrong and rather than shooting it out it should be running.
I could understand you wanting to keep the 30mm gun, but would suggest the removal of the 30mm grenade launcher to compensate.
I rather suspect that the addition of a thermal sight like the Catherine system fitted to T-90s and BMPs will be the only add on required to make this vehicle all weather day night capable. The missiles are IR guided and fire and forget so MMW radar or some such stuff is pointless... if the Catherine can't see the target there is no way the IR seekers on the missiles will get a lock anyway.
Another option of course... if we think about it... this is the VDV... best of the best, so perhaps the longer chassis troop carrier with vertical launch tubes on the rear and a very small turret on the front with thermal and TV optics to fire Morfei missiles.