He sold them to collectors for $100 per cartridge.
At that rate, 10,000 cartridges is a million bucks.
They sold out pretty quickly.
The redneck approach would have been
12 Gauge from Hell 3.85", bigger, more powerful.
1400-gr Darwin Slug at mere 1800 fps taught me a lesson in a single barrel.
IIRC that was with only 180 gr of RL-17, with filler !