Sounds like a pretty severe case of owner ignorance, to reload ammunition for his firearm using the wrong diameter of bullets. No reloading manual ever printed has neglected this fact, so he was either ignoring reloading data, or trying to repurpose the wrong bullet diameter to save some logistical headaches - his fault either way.

Not sure why a simple anecdote necessitates a handful of pictures and links to others’ work, but I guess that’s a thing some people do...