Common Handgun Calibers Converted to MM and Inches Handgun Cartridgeįortunately, understanding the conversions between metric and imperial for handgun calibers is quite a bit easier because there are far fewer common pistol cartridges than there are rifle cartridges.įor the most part, handgun calibers are either 9, 10, 11, or 12mm. 30 caliber cartridge, which isn’t actually correct at all.Īs you can see, the naming conventions of cartridges is complicated because ammo manufacturers like using clean, even numbers and to ignore the actual measurements.īecause the table above has to make some generalizations about particular cartridges, I’ve included the table below which lists each rifle cartridge separately so you can see the specific bullet diameter in inches and its exact metric conversion. The difference is that one measurement is the distance between the grooves (the cut out portions of the rifling in the barrel, and another measurement uses the measurement to the lands (the raised portion of the rifling). Converted to metric, that’s 7.82mm, but most people would refer to it as a 7.62 because of its military distinction. On this page we consider in detail all variants for convert 34. One millimeter is equal to 0.0393700787402 inches.

308 Winchester is so named because the bullet is. 34.9 (Millimeters, mm) - unit for measure distances, lengths, heights and widths in Metric Units. That’s because the naming conventions for many of the most popular cartridges bend the rules of measuring in order to come up with a nice sounding name.įor example, the good old. There are some things in that table that just don’t seem right. If you’re like me, looking at the table above starts to make your head spin. Rifle Cartridge Caliber to Metric Conversion Table Rifle Caliber Name The manufacturers of ammunition have done us no favors in making this easy to understand, but I’ve put together this handy resource so you can quickly see the equivalent naming conventions between mm and inches (caliber). This page will explain the problem as clearly as possible. Many shooters are confused because there are two different systems for measuring the bore diameter for a cartridge: (1) the caliber system measuring the diameter of the bore of the barrel in inches, and (2) the same measurement, but in millimeters.

.9mm in inches