In Editor: Place a Panther ("B_APC_Tracked_01_rcws_F") and a GMG Hunter ("B_MRAP_01_gmg_F") controlled by the AI. Choose a target and place it > 1000m away from the vehicles (more distance -> more discrepancy).
My naming of the vehicles:
Panther -> apc
Hunter -> hunter
Target -> tgt
Scenario 1
Via debug console type:
->"hunter doWatch tgt; hunter doTarget tgt"
->wait until gunner has aligned the gun
->"hunter action ["SWITCHWEAPON",hunter, gunner hunter, 3]; hunter action ["USEWEAPON", hunter, gunner hunter, 3];"
Scenario 2
Via debug console type:
->"apc doWatch tgt; apc doTarget tgt"
->wait until gunner has aligned the gun
->"apc action ["SWITCHWEAPON",apc, gunner apc, 3]; apc action ["USEWEAPON", apc, gunner apc, 3];"
In both scenarios the vehicles will fire the GMG. Watch the difference. To check, you can alter scenario 2 to HMG fire:
Via debug console type:
->"apc doWatch tgt; apc doTarget tgt"
->wait until gunner has aligned the gun
->"apc action ["SWITCHWEAPON",apc, gunner apc, 6]; apc action ["USEWEAPON", apc, gunner apc, 6];"