Wihill--I tried the 25 ACP plug with small rifle primers before I tried the Winchester 777 primers and it did very little to help with the crud ring problems in my 2 TC guns.
Scracherky: Which small rifle primers did you try? I tried Winchester small rifle with little improvement. I am now going to try some CCI small rifle primers. Hope they work as I have a bunch of them. I think I also tried Remington with little improvement. All the small rifle were better than the standard 209's but have not tried the Tripple Seven 209's yet. My Omega always has some crud ring ranging from terrible to just irritating. I have never been able to load a second shot without scrubbing the bore between.