I concur with the previous posters.

I successfully use the silver Gauge Mates to shoot 12 gauge reloads in my Baker 10 ga. Damascus SxS. The resulting "ridge" is minor, and doesn't affect reloading. Or, you can just discard the hull.

I used a Dremel for grind away a 3/8" half circle from the Gauge Mate rim, which facilitates case removal and reloading.

JERRY