Cylinder wobble? GP-100

I shot my GP the other day, reloaded 38, light starter loads. Got to the 11th round and the cylinder began to bind. I thought maybe lead from the reloads but upon closer examination, it appears the cylinder isn't turning true.
Ever so slightly but enough to rub the forcing cone.
Hoping dirt on the ejector rod??? anyone have thoughts on this?

Well,,,,,,,,,turns out there was a small piece of crud under the ejector star,,,,all is well. (so often it's the simplest of issues)

That's why I began carrying an old toothbrush in my range bag, especially when shooting reloads.