Somewhere near that time frame was an article talking about how shooting airguns at spent shot shells at 25-50 feet was like shooting a mile or more. There was math, I'm bad at math but it was something like 3" SHELL = 6' man, distances scale and projectile weight, etc.There was also an article about the 16" guns of battleships with similar scale - opposite end of course.
I've tried the 410 shot-shells at 30 yards and those are a serious workout with a 2400KT using wadcutters. I've tried 45ACP shells, soo, but the REAL hard targets were 380ACP "brass".