Looks like a storage area; otherwise, there would be more deformed bullets. Since there are several different calibers, it likely indicates a diverse arsenal and a larger troop size. The bullets have many cuts, so the plow will have distributed them much deeper. Many more will turn up; try testing with the Deep setting on the Deus 2 with the speed reduced to 1.5. If more bullets and some Minié projectiles appear, perhaps from the transitional period of bullet types from the mid-19th century onward...