got hold on a couple non funktioning almost complete automags that needed some love and care that got build together as a minimag pistol.

but heres my question... had some isues with fluxing velocity over crono and checked the regulator piston oring surface and found that it is somewhat irregular in surface like streaks frome lathe machining and checked at my working mag and found out that it too had slight irregular surface where velocity piston is seated but it works for that valve but caught my attention when two valves got the same type of streeking ore if this is a normal thing that other had stumbled upon also?

so is it just me that thought it should be smoth surface for the regulator piston oring ore is this a common thing and nothing to worry about?