What is the lowest number gauge shotgun?

Answer 1

This answer is a little more difficult to define than you may anticipate. Shotgun gauge is tied directly to Bore. Most people understand Bore to simply be a reference as to the diameter of the projectile, one should remember however that language evolves over time and what something means now is not what is always meant.

Shotgun Gauge is tied directly to an old-system of measurement which placed greater emphasis on projectile weight than diameter. This can be seen in old English 'Elephant Guns' which are commonly known as Bore-Rifles. Bore (and gauge) in this context references how many spherical balls of that size would be required to total 1-pound of lead. Thus a 12-Gauge or 12-Bore has an equivalent dimater to a lead ball weighing 1/12 of a pound.

Thus under that particular system of measurement, a 1-gauge would be as large as you could go, since at 1-bore you'd be 1 ball to the pound. You could of course make a bigger gun, but a new system of measure becomes necessary. In practicality however nothing even approaching this size has ever been used as a true shotgun as not only the weight of the gun, but the recoil would strain human limits.

However, 'Punt-Guns' were a sort of big-brother to the shotgun, these were essentually shotguns scaled up to the size of a small artillery piece and then mounted on a boat and used for harvesting ducks...by the flock.

In a realistic practical sense the largest (lowest number) gauges you are apt to find is the 12-gauge. While one can find 10-Gauge shotguns for sale they are returning to obsolecence after a brief resurgance in popularity due to the simple fact that there is nothing a 10-Gauge can do which a modern 12-Gauge cannot for less cost, weight, and recoil.