Having mistakenly shoved a .257" bullet into a 6mm-284 case, I'd think that it would be rather obvious that something was amiss. I believe the man would have noticed something wasn't right while seating bullets if there was a bullet of the wrong diameter in the box he was reloading from. But then again...

Don't be the darkness.

America will perish while those who should be standing guard are satisfying their lusts.