So I tested a couple new loads this morning for .45 in a few pistols. In all 3 pistols, both loads tested came out with the brass dirty with burn marks on 1 side of the top half of the brass. I'm using 200gr RN Plated bullets and Titegroup. I started out with 4.7 and 4.8 gr of powder. The load seemed a little light. Recoil was really light, but both loads cycled fine in all 3 guns. Is the load too light? Is the brass not expanding enough in the chamber and that's why I'm getting powder burns on the outside of the brass? Is my crimp too tight so it's not expanding enough in the chamber? Should I worry about it, or not? Input appreciated. Oh, if it matter these are all large primers and I'm using CCI's.