Hey Gordon, I know of a guy that makes custom plugs that are made for BH209, i am running one in my Accura right now.
He charges $13 to have one made. Let me get his email address and i will forward it to you.
Heres his custom plug,
The plug in the middle is the factory CVA Plug, the next plug on the right is the custom plug for the Accura,wolf,optima.
I believe Don is giving you tips on things to try before drilling the plug to the recommended .035" flash hole. A tight sabot will build more pressure VS the powerbelt and that extra pressure the sabot offers works excellent with blackhorn.
He'll get you all taken care of though for certain.