Bob I have seen the narrow tapered rib on all gauges 12 through 410 and in barrels 28 and more. That's just what I've seen and I sure haven't seen them all. There is no mention of it in TPS nor has it been found in Parker documents but it surely exists

Sounds like you have a wonderful 20ga

Here is the narrow tapered rib on a 1905 CHE 16 ga 28 that I will take with me for the next month. A favorite hunting gun.

Kind of nice wood on the 16

Here is another narrow tapered rib on a 20 ga 30" A grade

Also with nice wood

And some people like the engraving

That is a beauty, Bruce. It may seem odd to the members in the U.S., but even though I've been a PGCA member for years and kept my eyes open for Parkers I've only actually seen, in person, one in a grade higher than DH. A well worn AH about 6 years ago at a gun show I had to drive 12 hours to get to. There just aren't any up in northern Canada where I live. So please keep those photos coming. Its probably as close as I'll get to the high grades.

edit:You posted those A grade photos while I was typing the note above. Just stunning. Some day when I retire I'm going to travel down the east coast and hit all the big SxS shoots in the fall. It will be an education.

Bob I flew with the RCAF at Edmonton and spent time at RCAFB Cold Lake. Landed at Churchill on Hudsons Bay. Great times and great people. Spent many storms at Goose Bay in Labrador

Goose Bay, Churchill, Cold Lake, well, you've hit some of the best places in Canada! It is a great country, but could sure use more Parkers, Foxes, and Elsies.

I haven't helped you much. I have pulled three really nice Parkers and one wonderful Lefever out of Canada. The little DHE 20 ga 24" in the first photos spent 95 years in Halifax NS

Ha, so you're the one! Just kidding. I think Jack Cronkhite has brought a up a couple to make up for it. They made it up here on their own, but I've got a few that lettered as being originally sold in the U.S. so I shouldn't complain too much. I have to admit that I hate seeing the really nice ones leaving. Too much of the country's history gets lost.