but cerocoat or similar does not protect the bore and some are saying thats the part that rust!
Here is a couple of examples of my experience with barrels.
My mate bought a new tikka stainless ctr in 308. About a year later he bought a new blued tikka in 223.
I got a borescope about a year after that and we had a look at both rifles.
The stainless barrel was fine but the carbon steel barrel had some pitting even though it was a newer rifle and had fired less rounds. He didn't clean the barrels every time he used them.
He also bought a used sako trg. The rifle was mint on the outside and you could tell it hadn't done much as there was very little wear to the blue finish on the bolt or the stock finish.
When we borescoped it the barrel was very badly pitted, it still shot great though.
I have one of the older sako trgs that came with the stainless barrel from the factory.
I have it from new and it has fired over 4k rounds.
When I looked at it there was no pitting or corrosion, in fact there was very little sign of any barrel wear at all.