OK, since some folks seemed interested, I thought I start a thread on this subject. I ordered an assortment of gas control screws from the Browning parts dept. I placed the order last Wednesday, and the screws arrived today. Pretty snappy service, I'd say!
The part numbers are in the exploded diagram at the top of the forum, but for simplicity, they run from F141250020 to F141250210. There are 20 different part numbers. The SMALLEST port is F141250020, and the LARGEST port is F141250210.
I'll be updating this thread as I compare the port to my unmodified 16s, my chopped and reamed 16s, and let you know my results when I hit the range, which I hope will be Wednesday.