Hmm, is this with ACE or not? The magazine for the launcher consists of 8 missiles so I don't know why it would only be loading one at a time with the vanilla system.

I just tried this with and without ACE3 running and if you move the Tunguska near the ammo truck after firing off the missiles, it automatically refills them as you can see from the two images below. Could you test again with just the required mods? Also, how are you rearming them exactly?

https://steamuserimages-a.akamaihd.net/ugc/1754685185778679120/695331B44E3537D9349141891BD753998D83CA29/
https://steamuserimages-a.akamaihd.net/ugc/1754685185778679288/EF5C07117BA611EEF7505E1C5F0FF71B7C06A1DD/

Hi, thanks for taking a look.
I am indeed using ace.
For re-arm I use the ammo vic, ace intereact and 'Take ammo' 'Rearm' function.
I will take a look using only 3cb and Ace when I get chance and add comments.
Thanks again for taking a look.

No problem. Chances are it is the difference between the vanilla system automatically reloading the magazine, and ACE3's system and missiles. Potentially you may have to reload them one at a time for realism sake. Not sure. To test maybe try it with BI's AA tracked vehicle or a helicopter with missiles?