Couple years ago my model 12 223 had some ejection problems. The bolt would extract the spent casing but leave it sitting directly on top of the magazine follower. I had to pick it out with my fingers. I replaced the ejector with a new factory part, spring and ball too. Seemed to fix it. The old bronze part didn't show any wear, but the new part was made from a different material.

Now it's doing it again, same exact problem. Doesn't matter if I work the bolt slow or fast or gentle or hard. About half the time the spent casing is left being sitting on top of the mag follower.

Any ideas? It's not a cleaning issue, I keep this gun sparkling clean. I wish it would fling the old casing out like it's supposed to.