For assaulting an artillery position, sometimes snipers can get great shots on the crew. Infantry can also use what I like to call "smoke cover smoke", basically throwing smoke, running to the position, throwing another smoke before assaulting with an anti infantry or anti armor grenade before rushing their cover and taking a position to breath hot lead in their faces.
Tanks can usually sit a fair bit back, using an HE round to avoid wasting shells on nasty armor. However sometimes the artillery can spot the tank before its move and begin targeting it, Japan can use a Banzai rush - an excellent cannon fodder cover to move and assault, but when playing for another side it is best to create a confusing move, having a jeep/scout vehicle (even a truck) move around to draw artillery fire before charging with infantry (maybe getting some mortars on the emplacements too!).
You can combine techniques or see what works best for you, but for me those tactics work
