Talking about misinformation, stating that the 2 3/4" 20ga mag (1 1/8 oz) is "one of the worst-patterning shotshells" is totally at odds with what I've seen on paper. You'd expect to see more pellet strikes in a 30" circle vs a 1 oz 20ga load--but in my patterning tests, which involve actually counting pellets from the shells tested, you pick up not only more hits, but a higher PERCENTAGE of hits using the short mags. That's mainly, I think, because they're buffered.
Please understand that I'm not a huge fan of those loads, because they tend to kill on both ends, if you're shooting a light gun. But I used to kill a lot of wild pheasants with them, although I've found more reasonable solutions since then.
I believe all the "big 3" American makers (Win/Rem/Fed) offer 20ga short magnums.
