Siege tower ammo

I've noticed something interesting with siege towers that I'd never seen before. I was beseiging Mastia, and had 6 towers when Qarthadast sallied.

Rather than drop the towers and reform, I decided to see what would happen if I held onto them with autofire on. I had enough other troops to form a line in front. They attacked a few units at a time, and whenever they came within range the ballista on the towers would start picking them off, which is what I thought would happen.

Then after a while I noticed that the ammo bar for those units (prinicipes) was going down. Eventually they were empty, so I got my prinicipes to drop the tower and reform. As soon as they did that they had full ammo again, and were able to throw their pila.

Obviously the ammo bar initially refers to the tower, which must have a specified amount of bolts (which makes sense). I'd never noticed this before, as they generally don't have that long to fire before they reach a wall.

Does anyone know if gates and wall towers have similar limits on ammo?

Nope gates and towers have unlimited supply of arrow..
proven?
i played a siege battle in which my legionaires were in testudo right in front of 8 towers also in front of a gate on 3x speed for a hour (was very bored) and they were still shooting till my auxilaries took the walls...

That's the defender's advantage... it makes sense that they can supply a near-unlimited storage of ammo in their storage room under the city tower, the ammo is just a sharpened stick as long as 1 m, so they are cheap to made, and easy to storage...:laugh4: unlimited supply to impale all the attackers...

Siege Towers on the other hands, only had some ammos that their crew can carry... but in EB, the tower ammo are fewer than vanilla, and they didn't get the rapid fire...:wall: