I'd never heard of a "Carlo Gun" before. Saw it mentioned in a hyperlink in a War Zone story on the war in Gaza. It's a crude automatic weapon based on the venerable 9mm Carl Gustav M/45 (aka "Swedish K") SMG. From the article,
'In addition to taking on various outward appearances, the guns can also be adapted to suit whatever kind of ammunition is available. “‘Carlo’ submachine guns are most commonly chambered for the ubiquitous 9 x 19mm handgun cartridge... however, there have also been examples of versions that work with “other calibers, including .22 LR, .32 ACP, 9 x 18 mm, and 5.56 x 45 mm.”'
https://www.timesofisrael.com/say-he...or-terrorists/
This looks like something that a basic machine shop could crank out pretty easily in the later phases of the Twilight War. Apparently, all it takes to produce the Carlo is a drill press, some welding equipment, and a blueprint. From the article,
'Most of the current Carlos are based on designs from “American publications, which were readily available via mail order services, particularly during the 1970s and 1980s.”'
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