If you've read my recent reply to another post today, you may have noted that I have both an 1100 12 gauge Special Field and a 20 gauge 11-87 Upland Special. I've hunted and shot clays with both and have never had one malfunction.
The 11-87 20 ga digests mild 7/8 loads and 1 ounce field loads with no problems. It's extremely smooth and allows very quick second shots on missed clays (Yes, I've missed a few over the years, but rarely).
The heaviest rounds fired from the 11/87 have been 1 ounce Winchester Super Speed high brass field loads.
Picher