Been quite a few years ago but I had the HOTS (real bad) for a Remington XP 100. Hit one of the BIG gun shows in the Sacramento, Ca. area. Made the rounds, found the one I wanted, continued looking at the rest of the tables then went back and got the XP. Looked down the barrel and saw a few rust spots. No worries.
Just happened to have a new box of ammo with me.
Stopped on the way home in a big open area just off the highway and popped a few rounds. NO MORE RUST SPOTS!
Banging steel out to 400+ yards with a 10" barreled bolt action pistol? PRICELESS.