Handgun Accuracy Pet Peeves, Gripes, and Outright Lies

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A surprisingly small sight picture error can cause big misses down range.

A man has got to know his limitations. What drives me crazy about many gun reviews is how the shooter doesn’t realize his or her own. Consider this common observation about a gun’s “accuracy.”

“I decided to test the accuracy of this pistol by using a two-hand stance and shooting groups at a target 25 yards down range.”

Guess what? That’s doesn’t tell me Jack Diddley Squat about the gun. What it does tell me, and not very scientifically at that, is how good the shooter’s eyes are, how well they can hold, the quality of their trigger press, or maybe that they like to brag about their shooting skill. It doesn’t tell me anything because any combination of those factors in varying proportions could be contributing to the end “accuracy” result, whatever that may be. The one certainty is that it tells me absolutely nothing about the gun itself and it’s mechanical ability to shoot small groups.

The Sig Sauer P229 Legion will certainly shoot!

The Sig Sauer P229 Legion will certainly shoot!

Here’s the thing. There are three conditions that must be satisfied, perfectly, in order to get a reading on whether a handgun is accurate.

  1. The hold must be rock solid. Once aimed, the gun must remain stable.
  2. The sights must be perfectly aligned with an exceptionally precise point on the target – down to a fraction of an inch.
  3. The trigger must be pressed without any movement of the gun until the bullet is out of the barrel and on its merry way.

If you’re standing, using a “two-hand hold” it’s virtually impossible for all three of those things to happen, at least to the level of precision of a quality gun.

Accuracy illustrated

To illustrate the point, let’s just look at sight picture. I’ve got a Sig Sauer P229 Legion 9mm sitting on my desk as I write this. The front and rear sight are 5.7 inches apart as measured from the back of the rear sight to the rear surface of the front sight. Since three things need to be perfectly aligned – the rear sight, front sight, and target, we’re dealing with a proportional relationship between them and we can do some simple math extrapolating the effect of alignment errors 25 yards down range. Assuming we keep the rear sight anchored, if the front sight moves relative to it, just a bit, there will be a large variance in where the bullet strikes the target.

Handguns have a short sight radius. For example, this Sig P229 has a sight radius of 5.7 inches. If they're not lined up perfectly, results will vary by inches down range.

Handguns have a short sight radius. For example, this Sig P229 has a sight radius of 5.7 inches. If they’re not lined up perfectly, results will vary by inches down range.

How large? If your front sight is out of alignment by the width of a dime (about .053 inches), you’ll miss by 8.4 inches at 25 yards. OK, so that’s a big misalignment. How about the thickness of a sewing needle? One of those is only about 1/32 of an inch thick. That will cause of a miss of about 4.9 inches 25 yards down range. Even if your sight alignment if off by the thickness of a piece of paper, about .001 inches, that translates to a ¼-inch miss down range. When trying to measure the accuracy of a pistol, where good ones will fire five-shot groups of just one or two inches, clearly inches or even fractions of inches can completely throw off the results.

Now keep in mind that we’re just talking about minute differences in front and rear sight alignment. We’re not even accounting for “point of aim” variances. Considering that you can’t perfectly focus your eye on the rear sight, front sight, and target 25 yards down range, you’re going to be trying to aim at an imaginary point a fraction of an inch in size while it’s completely blurry. If you’re focusing on the target, one or both of your sights will be blurry because the human eye can’t focus on all three objects at the same instant. Get the picture? Or lack thereof?

So, what’s the bottom line?

Can you shoot great groups freehand? Sure. But if you shoot to the true extent of a gun’s mechanical accuracy that way, it’s almost certainly an accident.

Results obtained from shooting over iron sights, with or without a rest, are far more reflective of the shooter’s eyesight than any mechanical accuracy of the gun.

What these tests can tell you, in a purely subjective manner, is how easy a gun is to shoot accurately.

If you want to really understand what a gun can do, it’s critical to remove the human error factors such as hold, trigger press, and especially eyesight. When I review a handgun, I’ll often add a scope using a rail adapter just to completely remove that potential for sighting error. That one change alone can shrink groups up to fifty percent.

Tom McHale is a committed learning junkie always seeking a new subject victim. As a lifelong student of whatever grabs his attention on any particular day, he thrives on beating rabbit trails into submission. In between his time as a high-tech marketing executive, restaurant owner, and hamster cosmetology practitioner, he’s published seven books and nearly 1,500 articles about guns, shooting, and the American way.