Just the Basics - Accuracy and Precision

 

 

Accuracy

• Exactness.
• The ability of a measurement to match the actual value of the            quantity being measured.

Precision

• The state or quality of being precise; exactness.
• The ability of a measurement to be consistently reproduced.

I’ve started . . . and I mean just started . . . down the rabbit hole of long range shooting. My current weapon of choice for this endeavor is a Panther Arms AP4 .308.

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I’ve described it to varying degrees here, here and here. The last link has a title of “Training – Long Guns . . . and shooting the accurately . . . Part 1 – What does “accurate” mean?” Accuracy is simply part of this equation . . . there is also “precision”. So let’s spend a bit of time defining “accuracy” and “precision” and their place in the shooting community – particularly long range shooting.

Accuracy is the more flexible of the two terms because it is up to personal interpretation. If you take a walk through my last article referred to above – there actually is a place for “close enough for government work”. If you are talking about the arena I spend most of my time in, defensive shooting, you must be accurate enough to get combat effective hits on a defined threat as quickly as possible. This comes under Rob Pincus’ idea of a “balance of speed and precision”. It typically shakes out as 3-5 rounds, high center mass in an open palm sized group. Anything within that area will have a real effect on the threat’s ability to continue their attack on you. There is no need to take the amount of time it would take to make sure all the rounds created the smallest group possible.

What if your required POA becomes “the head shot”? I talked about that at length here. Now the size of your target has been reduced to something the size of a silver dollar. Here you must move past the level of defensive accuracy and place a “precise” shot to the ocular cavity. Something requiring a much higher level of skill.

So what does this look like on a target? Well, it looks something like this . . .

First let’s examine a target that shows a lack of both accuracy and precision.

Notice there is no pattern, no groupings . . . just a bunch of holes on a piece of paper. Now, given that the paper was placed at the 100 yard line, there is some level of accuracy and precision . . . but it is far below what we are looking for. The AP4 is capable of 1.00 MOA give or take a couple of tenths. When we achieve that, we are “there”.

Second, let’s look at a target that is “accurate” but not “precise”.

Notice that in both instances the rounds are within a 4” square (with one flyer), but their overall groupings are far wider that the 1 MOA of the gun. So while the groups are accurate – they are NOT precise.

Third, let’s look at a target that has “precise” hits but lacks accuracy.

Notice that target 1, with the exception of 1 flyer, there are 2 three round groups that are sub-1 MOA but the groups are high and left of the desired target – the 1 inch square in the center. These groups are VERY precise with one being less than ½” . . . yet it is NOT accurate.

Finally, let’s look at a target that is both Accurate AND Precise – within the capabilities of the weapon.

Notice that on target 2 the 4-round group is almost exactly a 1 MOA sized group, the capability of the gun. And, it is much more centered on the desired target, the 1 inch square in the center of the 4 inch square. The group is both Accurate AND Precise.

In the long range shooting environment – whether hunting, shooting competitively, defensively or using your skill as a designated marksman or sniper in the military – there are many instances where your ability to be both accurate and precise are required. And that ability like so many others requires good equipment, good instruction and trigger time.

Only YOU can take yourself to that level. I must admit I am enjoying walking down this rabbit hole much more than I thought I would. I suspect it will find its way into my range work on a regular basis and that a couple of firearms will find themselves upgraded to accommodate this new path.

In fact it was an upgrade to the AP4 that brought about the range session that created the targets shown. I was unhappy with the scope I had used in the long range shooting class. So, I upgraded to a Nikon Prostaff 5 with a Mildot reticle and a Nikon M-223 mount. I wish I could have afforded some of the $3,000+ scopes that were in the class . . . but I have enjoyed my marriage for too many years to break in a new wife at this time in my life. The short story is I was very happy with the performance of the Prostaff 5 and also with its price point. I’ll do a review of it in the not to distant future.

There is value in adding accurate and precision long range shooting skills to your skillset. It does not need to cost an arm and a leg and, you will learn far more about being deliberate, about ballistics and how a gentle breeze can affect your shot than you ever imagined! Enjoy!!