Sounds more like an 8 gauge pistol, gotta see what he does for a holster on this baby, I would love to make one as well but instead a 4 foot long 1911.
First thing I thought of when I read that was the force of that 35 pound slide coming back when fired. But then I thought about trying to rack the slide to load the thing, with a stack of railcar springs for the recoil spring.
Gauge is calculated by how many balls the same diameter as the barrel would it take to make one pound.
12 guage shotgun = 12 balls of the diameter of the barrel would make one pound.
10 guage would only take ten balls.
Five ounce ball would be more like a 3 gauge.
...and I’m with you on the 1911...