it honto look like serious bomb and it not dummy or hollow cause look at the heavy wooden supports it sitting on and see how the wooden planks under those are sunk into the ground from the heavy weight ka if some kind practice weapon it very very heavy. demo, ryo not think it practice weapon. have never see bomb casing quite like it. this is too small to be copy of the Fat Man atomic bomb use over Nagasaki, so not think it something like that either neh.
Your friend alway,
Yep, that is one big bomb there!