Handgun barrel issue...maybe

I have a CZ Scorpion that I SBR’d and got the HB Industries K conversion that came with a new 5.3” barrel

I’ve put about 300 rounds through it (100 suppressed)

I cleaned the barrel for the first time and noted a pronounced white streak along two of the rifling grooves. I can’t tell if it’s a divot or discoloration. Is this a normal imperfection type thing?

http://i67.tinypic.com/2ntbdcy.jpg

Attachment 53637