Any ideas?

[CSA2K]

Posting for a friend. Lives in Sharpsburg MD. Found in his yard..

 

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[CSA2K]

Oh yea says "puncture". Looks mostly iron with some aluminum maybe on the top..

 

[tamrock]

My first thought was, it was some kind of activating charge primer for an old fire extinguisher. I can't think why I thought that. Outside of that thought, I'm stump'd as to what this thing was made to do. I hope what ever it is, it's safe to handle.

 

[Doubter in MD]

Maybe an old sterno can? Just a wild guess, but it seems way to small for that.