I had the same opinion than Sambojin, but just tested the module once, on UV, and it seems ammo is quite low, indeed.
I finished with 3 unused shells (killed a caco with the chaingun, and did 2 radar shots, I think). there was still 24 shells on the floor, of course, but they only spawn after wave 2, and chaingun isn't reliable enough here.
btw, my build was SoB3, but I guess taking HR (or something else ???) makes you even more ammo dependent.
Also, I used both of my small medkits, since I didn't want to waste some more shells radarshooting.
I didn't try the N! version, but if you have the same ammo, I doubt it's possible without a zillion tries.