As Mobuck mentioned, I doubt it is paint. While I do not own one, I would be willing to bet it is not painted (at least not from the factory). Did you buy it new?
And no, that is not normal. I have never seen that on any of my guns, including ones that that over 10,000 rounds through them. It looks to have been knicked up/scratched (repeatedly).
Have you dropped it on the crown or banged it into something? Do you clean from breach to muzzle, or muzzle to breach?