Bullets Do Not Expand

by
posted on March 13, 2013
** When you buy products through the links on our site, we may earn a commission that supports NRA's mission to protect, preserve and defend the Second Amendment. **
lessons_ah2015_fs.jpg (2)

We gunners like to think of ourselves as very precise and accurate, especially when we talk of guns and such. Much froth and furor are put forth when we hear someone say “assault weapon” instead of “semi-auto rifle,” or “clip” when they mean “magazine,” or “bullet” when referring to a “cartridge.” The misidentifying examples are almost endless. But we are guilty of at least one mischaracterization as well. And that is the so-called “expanding bullet.”

Bullets do not expand upon impact. They deform—or more accurately rivet—when they encounter a resistance at terminal velocity. Balloons expand when air is blown into them. Wound cavities expand when bullets transfer their kinetic energy into a target. But bullets do not expand. Occasionally the word “mushroom” is applied to a riveting bullet. This, too, is misleading, since “mushrooming” describes more of an eruption rather than riveting.

During the muzzleloading era guns fired lead spheres known commonly as a ball. Throughout the literature of the day the lead spheres shot from rifles, pistols and canons were referred to as balls. Our term bullet is derived from the French word boulette—meaning “canon ball” or “small ball,” circa 1550 A.D. These largely pure-lead round balls often flatten to one degree or another on impact. Seldom is this phenomenon referred to as “expanding” or “mushrooming.”

I rather doubt that my little blog is going to change the lexicon of the day, especially since I have referred to bullets expanding thousands of times during my writing career. But in the interest of accuracy, we should realize that current terminology does not properly describe the observable fact of a bullet deforming upon impact.

Latest

W H2026 06 Hardware W3820 TAH 8188
W H2026 06 Hardware W3820 TAH 8188

Hardware Review: Henry H23 SPD PREDATOR

Check out Frank Melloni's review of the Henry H23 SPD PREDATOR.

First Look: Hawke Optics Vantage HD 30 SF

Hawke Optics has introduced its Vantage HD 30 SF, a second-focal plane riflescope line boasting System H2 optics for clarity.

Pyrodex Turns 50

Pryodex, the revolutionary black powder substitute that continues to be one of Hodgdon Powder Company’s most popular products for hunters who head afield with a “smoke pole,” was first introduced at the 1976 NRA Annual Meetings & Exhibits.

Know How: Understanding and Obtaining a Cold-Bore Zero

Have you ever spent hours at the range zeroing a rifle only to learn it is nowhere near center when you go to confirm it at camp? Many attribute this malady to scope shift during travel, and that can sometimes be the case. However, far more often this point-of-impact change can be attributed to the way we zeroed back home.

First Look: Winchester Air Rifles Single Action Western Revolver

Built to recall the Wild West, the Single Action Revolver from Winchester Air Guns is the perfect sidearm for junior-shooter summer fun.

#SundayGunday: Ruger Harrier

On this week's #SundayGunday, we’re taking a look at the latest modern sporting rifle from Ruger, the Harrier. Chambered in classic 5.56, this is a great rifle for any hog or predator hunter targeting large packs or sounders. Learn more in this exclusive video.

Interests



Get the best of American Hunter delivered to your inbox.