Clever, clever Mr. Hill. Cool corporate signature logo, too.
Wonder what kind of plastic that mag was made from. That's a realm of materials engineering that's seen a LOT of progress since 1953. Most of the clear plastics then were fairly brittle, were they not?
I was wondering about the plastic mag, as well. I'm wondering if the clear plastic was for demo purposes, let the Armory folks see what was going on. I can't see a plastic magazine surviving military trials in that era.
The pics come from a TFB article that didn't include any particular context or additional info that can't be gleaned from the photos themselves.
Looks like a simple, workable design, creating a nice compact package. TBH, a semi auto 9mm carbine, in a nice compact package like that, with nothing sticking down below the profile of the gun, would be a handy little plinker even today. I wonder what killed the project?
WarIsBoring has a bit better write up, but fewer pictures. Apparently, Hill kept on working on the gun into the 60's, and even tried to get FN to manufacture it, but they shelved the examples he loaned them and concentrated on cranking out the popular and profitable Uzi, which they'd licensed.
https://warisboring.com/the-hill-h15-submachine-gun-was-ahead-of-its-time/
View attachment 207367
At least FN gave a nod to the Hill patents when they filed the P90 patents.