Stop overloading your commonsense and blaming the army for being undisciplined or corrupt as there is no 'tactics' involved in placing an 12.7 or an MG on a Gun-Tower.
Unlike a tank or any other armored vehical, an artillery gun does not go into battle while it is still attached to a truck. The 12.7 is there for protection from air during move only. Once deployed, there are other measures which ofcourse will not be discussed. Any artillery unit or battery is authorized with a specific number of air defence weapons which may not be restricted to 12.7s only. So, just because you cant see a 12.7 mounted on every (Pakistani) gun-tower in the pictures that you see on the internet, it would not automatically imply that there is 'lack of funds,' corruption,' or 'lack of discipline' in the military per se.
Now, if you want that i should elaborate upon how we protect our guns from air attack to include the number / type of AA weapons authorized to a unit, just so that your ignorance can be tackled, sorry sir, that's not something i would like to dwell upon.
