Saw one a long while ago which made single slugs that were cut & swagged in one motion & were ejected by depressing a captive 'nose former' which was spring loaded & adjustable with a screw thread & locking collar. Pushing down against the lightish spring ejected the slug & on releasing it the spring returned it to the starting position.
It had no markings on it that we could see to identify a maker or retailer & so we assumed it was a bit of tea break engineering by someone who had access to some workshop equipment. No patent no. or anything either. Worked pretty well, one feature was that it produced a slight flare to the trailing edge of the slug so sealing was pretty good & we wondered if it had been done deliberately for a rifled barrel.
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