That’s roughly 12 inches. As in obsolete naval guns. It doesn’t *have* to be the full 300mm I suppose, the specification would include much more utilitarian things like 155mm artillery.
Did you read the story about the Aussies war on the emus? Machine guns failed. Maybe the 300 mm boom boom was needed.
“Thatâs roughly 12 inches.”
Wow. That’s one heavy high-capacity mag.