War machine models that do not have bases do not use the usual convention of measuring to the model's base. When measuring to and from the war machine, measure to or from the body of the machine, by which we mean the central part of the chassis or the weapon itself (ignore any spikes, piles of cannonballs, sprockets, banners and so on).

When firing a war machine's weapon, ranges are measured from the muzzle of the gun (in the case of a cannon, volley gun or similar) or the crossbar (in the case of a stone thrower or similar catapult). If your war machine is particularly unusual and does not have any of these features, you should choose a suitable point from which you will measure all your shooting attacks, so long as you are consistent.