The 3-inch 20-gauge Model 21
Published comments by Jack O'Connor and Warren Page

Jack O'Connor

Outdoor Life November, 1951; page 66.
...One big concern has been experimenting with the 20 gauge guns chambering 3-in. shells containing 1 1/4 oz. of shot. Get a load of that! ....

Outdoor Life, March, 1958, page 114

...I borrowed a Model 21 for the 3-in. shells from Jack Boone, Winchester sales manager, some years ago and liked it so much that I bought one. Winchester was a bit skeptical about making it up with 26-in. barrels, but did so anyway. Barrels are bored modified left and full right and the gun weighs 6 3/4 lb. Both barrels pattern beautifully with either 2 3/4 or 3-in. shells.
    The little gun is the finest all-around shotgun I've ever owned, and I use it on everything from quail to ducks about three fourths of the time....

Complete Book of Rifles and Shotguns, 1961 First Edition

...In the old days many citizens liked 3-inch 20- and 16-gauge shells with what were then considered heavy loads of shot for duck shooting. Repeaters wouldn't handle the long shells and they died off. In 16 gauge, so far as I know, they have never been revived, but for years various knowledgeable shots around the Winchester and Western plants were using Model 21 Winchester doubles for 3-inch 20-gauge shells on ducks, and a few years ago these manufacturers put the shells on the open market.
    I have a 20-gauge Model 21 for the 3-inch magnum shell and I love it...

Outdoor Life, September, 1965, page 74.

...    Winchester executives are responsible for the current popularity of the 20 gauge Magnum with the 3-in. case. Not long after World War II, I began to hear by the grapevine that some of the big wheels of Winchester-Western had been getting Model 21 Winchester doubles made for 3-in. and had been shooting 1-1/8 oz. of shot on ducks with great success. I borrowed a long-chambered 20, used it, and liked it. As we have seen, I have had such a Model 21 for over 10 years...

Warren Page

Gun Digest, 1954 "What's New with Winchester?  p. 184-185
...Another Winchester-Western development fills the needs of fewer shooter, but it may serve to stand part of the shotgun world on its tin ear.  That's a 3-inch 20-gauge shell, a 20-bore Magnum.

     It's not exactly new, in that such loads have been field-tested for a number of years by top brass in the Olin Industries plants, among them devoted and skilled waterfowlers like John and Spencer Olin, Mississippi Flyway duck shooters who followed them into a blind may have been mystified by the extra-long 20-gauge empties--not that the expert shotgunnery of the Olins leaves many empties littering the blind even on a limit day-but keeping up this small mystery was all to the good, since long testing insured that there were no bugs left in the load before its release to the public.

... The only gun factory-chambered for the new 3-incher right now is Winchester's Model 21 double, the only top-quality side-by-side made in this country today, and the 21 is of course no gun for the gink with a slim wallet, not at a starting price of over $300.   The birdies tell me that Winchester does not at present intend to chamber the Model 12 slide action for the new 3-incher; and what the possibility is of re-chambering other doubles or over-unders for the new hull remains to be seen.  No dice for any lightweight or any but the stoutest actions, that's for sure.  So the 3-inch 20-gauge is a specialty for the well-heeled so far, but what a specialty for the Model 21 fan for his second tight-bored set of barrels!