Help to ID shells on lamp

[Georg]

I am not sure where to post this, but it kind of fit here. I came across this lamp at a garage sale on the way home from work. I think that I am going to try to put it back together. Can anyone help me to ID the large shell, it is 8 ¾ ‘tall and the bottle down neck opening is approx.3 ¾ cm. I think that the two smaller ones are 50 cal (right?). I do not know how it will turn out, but for a buck, I will give it a try.

[zwerge]

It looks like an American 37 x 223R anti-tank casing.