Here is something interesting. I used normal difficulty, custom battle, flat arid map and took a v1a2 pav xbow 20x3 deep. I gave the ai a v0a2 xbow which is in 20x3 deep as well, marched up to a distance of 2 tiles away and both units started shooting. At the point I ran out of ammo I had killed 25 of the ai's men and lost 26 men. However, the ai still had ammo, and the reason is that the ai was only shooting a projectile on every other reload/fire cycle. The ai unit would go through the whole reload/aiming cycle, but when it said "firing" the men just stood up and didn't shoot. This is probably why many SP players say the ai has more ammo. The ai in fact had a lot of ammo left and kept shooting for another 7 to 10 min, but it only generated 6 more kills with all its remaining ammo because the unit went to exhausted soon after I ran out of ammo. What's interesting is that the ai kills kept pace with my kills while we were both shooting. I don't know how many men were firing in each volley, but neither unit had all men firing on a volley, and the ai unit seemed to tire as fast as mine, although, I had a slight disadvantage in fatigue from marching to the ai. I didn't get the impression that the ai was getting more kills per volley than I was, but it might have been skipping many of the no kill volleys. The ai did get some no kill volleys, but I got a lot of no kill volleys. I would estimate that 1/2 of my volleys got no kills. I'd have to look at the replay again to say for sure.