M10 (P50/M12) Pump Action Slingshot Rifle Update

After racing back to NJ from Michigan and diving headfirst into my projects and spring cleaning, I haven’t really taken the time to post a bloggy update on my projects. I won’t rattle off all of them just yet, that’s for another day, but I do want to give a status report on where I stand in the build process for my J√∂erg Sprave-inspired apocalypse defense weapon: the M10 Pump Action Slingshot Rifle.


Being in the United States, however, getting my hands on M10 hex nut ammunition is harder than in Bavaria. Home depot’s pricing on metric hardware is quite frankly a rip-off, so I went with the next best thing: half inch hex nuts. Although 7/16″ nuts would be a closer substitute for M10, that particular fractional size was in short supply when I went shopping. I figured I’d go big or go home.

This raises a decidedly uncommon problem, however. What do I name my creation if I can’t call it the M10 shooter? Half inch threading corresponds to 12.7mm, and neither rounding up nor down seems to produce an acceptable moniker. M12? M13? I don’t really like either, and since I’m not in metric anymore, there’s little reason to keep the “M” in the designation. So let’s use the ‘murican convention. Half inch nut = .50 “caliber”. I’m calling my creation the P-50, P standing for plywood.


That important matter settled, I am currently drilling and shaping all the bits in the trigger group, as well as grinding/drilling/cutting all the features on the outer panels. There’s a bit of trial and error, which is why I wasn’t able to completely design the P-50 on paper before putting saw to wood. The overall form of the weapon is completed, however, so you can get a sense of the unwieldy and hilarious size of it.

Tomorrow I will be cutting out the slit for the paracord ‘sling’ to ride in, and hopefully finishing up the trigger mechanism. I expect another 2 days after that to get the theraband cut, and the slingshot forks/pump mechanism completed. Testing is optimistically slated for next week Tuesday.

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