Around the world and throughout time, people have tried to take what is a good invention and make it better. This is only natural- we refine, create, refine and create some more until we find that perfect specimen we are trying to make. We constantly seek perfection in art, literature, science and tools. Occasionally, we hit the mark and create better things- vulcanite pipe stems to replace horn and amber, plastic tupperware to replace pots and pans, and sliced bread all improved upon the idea that preceded them.
This, however, is not that kind of story.
The 16 gauge shotgun has a nominal bore diameter of .662 inches. It is smaller than the 12 gauge and larger than the 20 gauge. Shotgun gauge is a measure of the diameter of the bore in relation to how many lead balls of the bore diameter would equal 1 pound. It was supposed to be the best thing to happen to the upland bird hunter. It worked on paper and was flawless in design. Swift, light handling guns were designed for this cartridge. The only problem was, it just never caught on. While the manufacturers were happy to push what seemed to be a bright new chapter in shotgun cartridges and arms, the consumer was reticent to commit. This has happened three times- once in the 1920's and secondly in the 1960's and in the late 1990's. Remington Arms Company is the group mainly responsible for keeping the interest of the 16 gauge alive/revived at these different times. But each time, it was placed in the spotlight to the "oohs and ahhs", and each time, interest died quickly.
No matter the time, it never caught on for many reasons:
Payload
First, the average shot payload for the 16 gauge is 1 oz. of lead shot. This is all fine and dandy, but the hunter typically wants all the power he could muster for the task at hand. So while you could go and hunt quail or other smaller birds, this gauge was lost on the duck hunter who would rather have a 10 gauge or, more likely, 12 gauge. You can stuff more shot into the shells for these gauges; in theory, improving your chances to add to the game bag. In defense of the 16 gauge, there are magnum shells available with 1.125 and 1.25 oz(s). of shot available to the consumer.
Recoil
Second, the 16 gauge has, more or less, the same amount of recoil as the 12 gauge. Consider: many of the guns that were manufactured in the 16 gauge were mainly either side by sides, over and unders or pump action shotguns. In order to attract the hunting crowd, the 16 gauge was built on a smaller frame to reduce the overall gun weight. When you drop the weight, the recoil increases. Hence, the kick is about the same as the heavier 12 gauge guns.
Performance
Third, the 16 gauge does not pattern any better than a 12 gauge shooting the same amount of shot. In fact, it isn't better and may suffer, some would say slightly, from ballistics that cannot be overcome. The problem is that the cartridge itself, never more than 2 3/4 inches in length, cannot produce anything more than what it does because of the relationship between the diameter of the bore and the actual height of the shot charge itself. It is almost an occult science, determining the relationship between the shot column height and diameter; regardless, this is the malady and there is no cure.
Shells, shells, shells
The fourth problem concerning the adoption of the 16 gauge is shell availability. In modern times, it is possible to seldom be far from a store of some type that can accommodate the needs of the 16 gauge shooter. However, one may not be as lucky and find themselves on a hunt without any shells readily available. Not so with the 12 gauge, which is nearly universally carried by merchants everywhere. Also, the 16 gauge, due to low demand, tends to cost more per box than either the 12 or 20 gauge shells.
Target Shooting
Lastly, the 16 gauge was never given special recognition for being its own gun; as a result, it was never given its own class in skeet shooting, which shoots events according to gauge, or trap shooting, which only uses the 12 gauge. Hence, with no real target shooting game devoted to it, the 16 suffered into near oblivion.
These problems notwithstanding, the 16 gauge has a devoted fan base who use the gun as it was intended- upland hunting and other wild bird shooting. For them, it is a matter of using your grandfather's old double, or perhaps your Browning Sweet Sixteen autoloader you were given as a kid. Maybe you have a 16 gauge built on a 12 gauge frame and do have lower recoil. While reloading supplies are not as readily available, they can be had, which makes shooting the old gun less expensive than it would otherwise normally be.
It looked good on paper, but never quite made it out of the shadow of the 12 gauge. It never became the sliced bread of the shotgunning world. It can't hold a candle to Velcro, but it still does exist, if only as a testament to how things shouldn't be.