Took some photos, will make explanations easier. That is a 50 cal for scale. I have three rulers which are usually sitting on a shelf above my desk and they are all missing.
This is the top of the shell where they blow torched about an inch down. I'll have to clean up these threads to get the fuse screwed on and then probably fill it with JB weld unless someone has a better suggestion.
Here is with the fin broken down. The gas check goes into the groove a little over halfway up the shell. These are expandable so I can put a new one into the groove. You can buy a 500 count box of them on gunbroker if you have need of them, not sure why anyone would but hey, they are there.
And the fin and shell assembled. May not be the correct fin for the shell but I don't care. Listed as a US Navy mortar fin, also used by the Britishfor HE rounds.
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