Monday, December 08, 2008

Size Matters

Over on Ballistics by the Inch, a couple of enterprising fellows have conducted experiments to check on the old question about how much barrel length affects bullet velocity when shooting.

Their protocols are simple, and the results are interesting, and maybe a little more surprising than a lot of people would expect. Basically, the same bullet out of a short barrel is slower than out of a longer barrel. In some cases, the difference between a two-inch snubbie and a rifle-length bbl. can be more than twice as much.

Interesting reading for gun-nuts and mystery writers. Check it out. And thanks to Todd for passing along the link.


Worg said...

Doesn't that just kinda stand to reason? This probably holds true as long as there's a "bang" when the bullet exits the barrel, because there's still expanding gas pressure there.

Gas under pressure is what causes the acceleration. When the bullet exits the barrel, pressure is equalized, therefore the longer the bullet is under pressure from the gas, the faster it will go.

Maybe I am missing something here?

Dan Gambiera said...

Worg, what's important here is not "whether" but "How much". Quantifying it with different barrel lengths and loads lets you make better decisions about carry options.

Steve Perry said...

Yep. A three-inch barrel is not much of a difference than a two-inch snubbie, viz concealment, but the added power might be worth the investment.