I've read that you should clean down to bare metal after every shot for 200 shots. I've also read that you should clean after 10 shots and just about every interval in between. I've never done any of that with new rifles and I'm happy with what I got.
I've also had a LOT of used rifles that I bought from guys who thought they wouldn't shoot, and tuned them up so they shot just fine.
I've have a 6.5mm milsurp that you can drop a .25 caliber bullet through and it shoots like it was a varmint rifle.
I doubt you can really mess up a barrel usin' factory ammo, and keep the visible copper or lead cleaned out.
