I made the trigger for you, It should works 100%
--Server side
function cmdArmedPed(player,_)
local x, y, z = getElementPosition(player)
local thePed = createPed(0, x + 1, y, z)
setTimer ( function ( ped )
giveWeapon( ped, 31, 5000, true)
-- Make him shoot continuously
triggerClientEvent(player,"onPedShoot",player,ped)
end, 100, 1, thePed )
end
addCommandHandler("armedped", cmdArmedPed)
--Client side
addEvent("onPedShoot",true)
addEventHandler("onPedShoot",root,
function (ped)
setPedControlState( ped, "fire", true)
end)