Odd Bullet, Shot and Cartridge Info
Rifle barrel inside diameter is measured in caliber which is a measure of an inch (.50 caliber is .5 or 1/2 an inch) or in NATO metric units (7.62mm = .30 caliber
5.56mm = .223 caliber) but shotguns are measured in gauges of course, and this is where things get strange.
The most popular shotgun gauges are 10, 12, 16, and 20....................... We'll get back to .410's later!
When shotguns were invented, the way they were "gauged" was by how many lead balls the size of the bore were required to make a pound.
The larger the bore the fewer balls; a 10 gauge took 10 lead balls the size of the bore to make a pound, a 12 gauge took 12 balls, etc........
Now back to the .410, now of course it didn't take 410 lead balls to make a pound........ The .410 gauge is a misnomer, for .410 is the caliber, .410 of an inch.
NATO measures the bullet and cartridge assembly in this manner: 7.62mm (diameter) x (by) 51mm (length), which is equivalent to a .308 caliber cartridge.
If folks read this, I may add more cool facts.
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