Gauge is a measure of shotgun caliber.
A smaller gauge number means a larger shotgun, a larger gauge number means a smaller shotgun.
Shotgun gauge is determined by taking a pound of lead and creating a set of lead balls exactly the diameter of the inside of the shotgun barell.
If 12 lead balls weigh one pound, the shotgun is said to be 12 gauge. If 20 lead balls weigh one pound, the shotgun is said to be 20 gauge.
| Shotgun Gauge | Bore Diameter |
|---|---|
| 10 | .775″ |
| 12 | .729″ |
| 16 | .662″ |
| 20 | .615″ |
| 28 | .550″ |
| 67 | .410″ |
.410 caliber is an oddity among shotgun calibers in that it is commonly referred to by its diameter in inches instead of its gauge number.
Shotshells and Ballistics
There is a bewildering array of commercially loaded shotgun shells for sale, from the .410 to the 10-gauge. In fact, there are more types of shells and shot sizes on the market now than ever before. With the overwhelming selection of shells available, here, finally, is a practical, reasonably priced book that makes sense of it all. It lists commercially available shotshell loads from the .410-bore to the 10-gauge, in all shot sizes available, different shot types (lead, steel, bismuth, tungsten, and others) so that the shooter or hunter can quickly find what will be best for the gun he has and the game or targets he wants to shoot. Each shotgun shell with each loading has its own table–over 1,600 tables!!–showing shot size; weight of shot; recoil; average number of pellets in the shell; manufacturer’s order number; shell length and type of hull; type of wad; and whether the shot is buffered or not. In addition, each table contains data that details velocity (in 10-yard intervals from 0 to 70 yards); average pellet energy; and time of flight in seconds. This book includes complete ballistic tables for every hull length and every shot-size load made from the following manufacturers: Aguila Ammunition, Armscor, ARMUSA, Baschieri & Pellagri, Bismuth Cartridge Company, Brenneke, Clever s.r.l., Dionisi, Eley Hawk, Estate Cartridge Company, Federal, Fiocchi, Gamebore, Hevi-Shot (now loaded exclusively by Remington), Kent, Lightfield, PMC, Polywad, Remington, RIO, RST, Sellier & Bellot, and Winchester. In addition, this informative reference contains authoritative articles on the history and development of shotshells and the components and technical data that govern the production of shotshells. Never before has so much information on shotshells and ballistics been placed in a single book. Accentuated with photos from the field and the range, this is a reference book unlike any other.
