A fair bit of chem stuff (ww2 mostly) had fairly thin walls so tends to be rusted out.
Things like Mk 1 chemical mines, 65lb light cased aircraft bombs and 400lb SCI's (flying cows) tend to be very rare in good condition. They just rust away. Thicker stuff 18pdrs, 4.5" shells, most of the German & French stuff tends to be around in varying condition. Some items are really common (German 10.5cm projo) and some less so (French 120mm projo).
Things like Mk 1 chemical mines, 65lb light cased aircraft bombs and 400lb SCI's (flying cows) tend to be very rare in good condition. They just rust away. Thicker stuff 18pdrs, 4.5" shells, most of the German & French stuff tends to be around in varying condition. Some items are really common (German 10.5cm projo) and some less so (French 120mm projo).