Its pretty simple, cut the top off an aluminum beer can, and fill with a cement mix. I have read that some use sand and then top it with a cement cap, but I have also heard that the can comes off like a sabot and lands in a flat plate a few feet from the muzzle of the mortar.
I heard that readymix turns to gravel, and that plaster of paris is best.
I decided to use type n mortar because it was cheap and I had a bag sitting around.
I tried shoveling some mortar in wet, and did a few with dry mortar and adding water.
The second was was easiest and fastest. I won’t know which is best till I get some field time.
Update:
For general shooting both ways works well. I think that the wet mortar way is best, but not enough to make a difference.
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