[44 AMP]

Rouge on the inside of a case is of no concern. The powder doesn't care, the bullet doesn't care, nor the case or the gun. Any possible erosive effect is completely overshadowed by the erosive effect of hot powder gas at thousands of PSI pressure.

I used the red media in a rotational tumbler for decades, only switching to the light colored "corncob" stuff when I went to a vibratory "tumbler".

The "half moon" dent on the primer is a result of something being misaligned or improper. Which "hand primer" do you have? Bench mounted or hand held?

the dent comes from the primer punch not being centered on the primer. This is normally because the case isn't in the right place in the shellholder or the shellholder isn't in the right place in its mortice. Check for dirt/crud buildup, especially in the shellholder itself. A little bit of crud in the groove and the case goes ALMOST all the way in, but is off center enough so the primer ram leaves a mark.

Another possible cause is not having the right primer punch installed. Older priming system often came with 4 punches. two of each size. one flat faced, and one with a curved (concave?) face for the old style primers that were rounded. Today the flat face primers are the standard. Using the "wrong" punch will still seat the primer but will usually leave a mark, even if everything is lined up properly.

The mark is not a concern for safety. it just looks bad.