Every shotgun hunter knows the 12 gauge and 20 gauge. Most are familiar with the 10 gauge and have at least heard about the 16 gauge and 28 gauge. But almost no one knows the 68 gauge, although they’ve probably seen and even shot one.
How is that possible? Because the 68 gauge is commonly known as the .410 “gauge,” which really isn’t a gauge at all. The little .410 shotgun, for some odd reason, is named for its bore size, or caliber. This is standard when identifying rifles, but not shotguns. But for clarity, perhaps it should be.