Mark inside Redding Type S Die

[CShooter92]

I was sizing a bunch of Dasher brass the other day and noticed this scuff mark inside my Type S sizing die. The inside of the die seems to almost be stained a black color, and this scuff looks more typical silver color. I've tried G96, Wipeout and scrubbing with a bronze brush. Nothing affects or cleans the finish.
I've reached out to Redding, just wondering if anyone has seen something similar and has an easy solution?

 

[Wheres-Waldo]

How does it size & feel when sizing? The inside of the die doesn’t look amazingly smooth.

I’d imagine it’s carbon, but your attempts to remove that should have been at least somewhat successful.

Are you cleaning brass before or after sizing?

 

[CShooter92]

It feels pretty normal actually.

I clean my brass before sizing in walnut media, and after sizing to remove the lube.

 

[RldrNewby]

It feels pretty normal actually.

I clean my brass before sizing in walnut media, and after sizing to remove the lube.

Don’t have my readers on, but it almost looked like pitting to me. If you were to take something like a straightened out paper clip (with a polished end so it won’t scratch the surface of your die) and lightly moved the paper clip across the area in question inside the die, does it feel like the paper clip is falling into a pit, or hitting a raised area of resistance?

If it’s for sure pitting, I might would email Redding Customer Service, explain what your’re seeing, & provide them with some pics. Maybe they can send u a replacement along with an RMA pre-labeled return package so you can mail them back the one you currently have?