Is over-penetration is a point of contention or an overrated concern?
Gun scribe Richard Mann examines over-penetration during a time of conflict ...
We talk about it all the time, but is over-penetration really something we should worry about in a self-defense situation?
A bullet passing through a threat and continuing with the potential to cause unintentional damage to a bystander or object is a situation commonly described as over-penetration. The occurrence could be a bad thing if you shoot someone who is attacking you while your wife is standing behind the attacker. On the other hand, a bullet that passes through one bad guy and strikes another could be a good thing if the two are lined up to beat you with a claw hammer. Statistically speaking, neither incident is likely to occur.
But let’s imagine a crazed murderer breaks into your home, and you shoot through him. Could that bullet continue through a wall and hit a family member or neighbor?
Sure. I investigated a shooting where a
9 mm full-metal-jacket bullet passed through a car’s windshield, head rest, back glass and the exterior wall of a nightclub. Over-penetration has the potential to be a problem, but its relevance is a point of contention—even among writers who regularly appear in this magazine.
Fellow gun scribe Bryce Towsley believes, “Over-penetration is every ambulance-chasing lawyer’s best friend. In a fight you own every bullet you fire, and if one goes through the target and hits an innocent behind, it’s your responsibility. You will have enough to think about during a fight for your life; keep the bullets in the bad guy.”
Gunsite instructor and former Border Patrolman Ed Head has a different opinion. “I like to say over-penetration is overrated. Especially in a police context, worrying about whether a bullet will over-penetrate—when many of the rounds police fire miss the bad guy and endanger everyone in the neighborhood—doesn’t make much sense. In my experience, lack of penetration and incapacitation are the real issues.”
Statistics related to shootings seem to back Head’s take on the matter. Missing happens much more often than wounds from over-penetration. Nationally, cops miss the bad guy about 75 percent of the time on average. It’s reasonable to assume you may not shoot any better in a high-stress situation. When you miss, a bullet’s ability to over-penetrate is of minimal concern; it will hit whatever it hits at full force.
While a bullet’s ability to penetrate is certainly related to its ability to over-penetrate, it’s also related, in part, to what makes it effective against a threat in the first place. Echoing the words of one of the greatest handgunners, Sheriff Jim Wilson sums up the need for adequate penetration by recalling, “Elmer Keith had it right; an exit wound lets more blood out and more air in.” After all, our goal when we shoot an attacker is to stop the attack. We increase our odds by using ammunition that has the best chance of bringing about that stop.
All these experienced shooters are worth listening to, but I trust evidence more than advice. I conducted a series of tests in order to see firsthand what, if any, real concerns over-penetration might present. The results, though not definitive by any means, do give a glimpse into the over-penetration potential that exists with defensive-handgun ammunition.
Get the results of Mann's over-penetration examination on the Shooting Illustrated website.