Was that Federal Aluminum case ammo?
Yes.
I'm not even going to fight it by trying to tweak things. I'm tired of fighting guns that are picky on ammo. As you would know the aluminum has a kind of matte finish, not shiny like brass. So apparently when it gets up to where the mag spring compression is least the extra friction inhibits feeding. Seems strange given the strength of the mag spring. I usually use an Uplula just to be able to squeeze the 10th round in.
I will use it in other guns. I have 9mms Sig P250 Compact and a Ruger LC9S that have never failed with any ammo in about a 1,000 rounds each.
I'm disappointed in the Rami with respect to this and trigger bite. But overall it is still decent and I love it in single-action.