Funny, had not heard the old “fire a few jacketed rounds at the end of practice to clean out the lead “ in years. That was taught in the academy back in the 70s for our .41 magnums. Guess they were onto something then, but we still had to clean the bores.
I only ever clean the chamber and ramp/breach face. And outside ligs and what not. But inside the barrel I only ever run bore snakes through all my pistols a few times. Never use rods and brushes, never a problem
Probably shouldn’t over clean but I would think for storage, you’re going to at least want some oil in the barrel. A bullet isn’t going to clean the grooves.