It really wasn't chambered for 32 ACP but it will fire & eject them though the case bulges .
Sumthin' ain't right. COMMON Semi-auto's "tend to" use straight-wall, cylindrical cases that headspace on the front edge of the case rim. A .32 ACP "should not" do that in "the other common" semi-auto = .380 ACP. Looks just like the 9 mm Parabellum, but a coupla silly millimeters shorter, hence "9 mm
Kurz".
Absent repeatable headspace, firing pin strike would be erratic. Yet you don't seem to have that problem?
Now.. Korea... In addition to North Korean and Chicom forces mostly armed with Soviet Bloc weaponry .. and copies, there were. if memory serves, 13 "United Nations" Armed forces involved as well with European and US arms.
Besides - it need not have BEEN any body's "military or police" issue.
So the maker could have been just about
any country.
Some few semi-auto were chambered for "bottlenecked" pistol / machine-pistol rounds. These can headspace on their shoulder .. OR on the rim... depending on the designer.
Examples: See 7.62×25mm Tokarev, common to handguns and machine-pistols. Not the only player. Just one of the most widely seen.
Time, and past the time, you provided photos and markings, Pilgrim.
This will not be a "mystery" once enough expert eyes have sight of the evidence.
"Safe" doesn't seem to need a barrel-liner. It simply needs ammunition that FITS!
ELSE one makes a new barrel.. because the CHAMBER has to fit some other cartridge.
Ignoring those "basic landmarks" is about as UN safe as one can get -
IOW the PRIMARY "headspace" problem is between your EARS....
You can guess what REALLY needs "relined" if that message needs stronger conveyance from someone less genteel and diplomatic than I?
