In the world of firearms, telling fantastic tales of paper targets perforated with unlikely small group sizes is the shooter’s equivalent of fish stories. In the worst cases, a two inch group at the range somehow shrinks to half its original size by the time the account of the range trip is transcribed to an email or forum post. But even honest, well-intentioned shooters can provide misleading information out of ignorance or apathy by leaving out important details of accuracy testing.
Because accuracy is such a universally pursued goal across all shooting disciplines, you would think that there would be some generally agreed upon standards for measuring it. In the case of measuring the actual shooter’s skill, standards do exist in the form of the various shooting sports. But the shooter is only half of the equation. The gun itself is the other half, and that’s where we get into the rather imprecise business of shooting groups.
While it can be used as a way to practice marksmanship or to diagnose shortcomings in technique, what we’re looking at in this post is the other common goal for shooting groups, and that’s to determine “mechanical accuracy”, or the inherent capability of the shooter’s equipment when the shooter is eliminated from the equation; whether that’s ammo, sights or optics, or the firearm itself.
In the most basic terms, “shooting groups” is the process of firing a series of rounds at a target in an attempt to establish a pattern. A pattern of hits that are grouped close to one another indicates mechanical consistency. If that group is also close to the spot where the gun was aimed, then you have an accurate group. No problems so far, right? “Everybody knows how to shoot groups, Chris. Nothing to it!” So what would you think if I told you, “This AR is really accurate. I just shot some groups over the weekend and it’s a half-inch rifle”? Some people might think that sounds pretty accurate.
Well, what if I then told you that the so-called “group” was only two shots? And I was shooting from 25 yards away. With custom hand-loaded ammo. And I dismissed the “flyer” round that struck the target a foot lower than the other two hits. That’s not so impressive anymore, but this is the kind of information that is often conveniently left out when relaying range reports.
Whether the deception is intentional or not, without any standards for measuring groups that are universally practiced and understood, shooters often give one another “accuracy reports” that are next to meaningless. As a result, the shooters on the receiving end of these reports are forced to fill in the blanks with their own assumptions, which may or may not be correct. This can also happen to the original shooter himself if he fails to note all of the important details in his records. It’s easy to end up with overly optimistic expectations of your own equipment if you happen to misremember, for instance, that your deer rifle is capable of two-inch groups at 200 yards instead of the 50 yard range that was actually used when you sighted it in.
Maybe one day, some genius will come up with a brilliant, universally useful method for shooting groups and convince everyone in the shooting world to adopt it. I am not that genius, so I’m not going to suggest a standard for you to follow. Instead, I’d like to humbly recommend a few bits of information that you might consider when you’re shooting groups that will help keep your records accurate and your range reports honest.
At minimum, any accuracy report should include the following details:
Firearm used: Be specific, especially if the firearm in question has a lot of variants like barrel length, type of rifling, era of manufacture, etc.
Ammunition used: Include brand, bullet type, and bullet weight. Bullet velocity is also helpful to know in many cases.
Distance to target: It’s often assumed that groups are shot at 25 yards for handguns and 100 yards for rifles, but this isn’t always the case.
Position of gun and shooter: Were the groups shot from a rest or bipod? Prone or from a bench? When testing a gun’s mechanical accuracy, the shooter should be eliminated as a variable in the equation as much as possible. That said, groups don’t have to be fired from a rock solid hands-free Ransom rest in order to provide useful data. On the other hand, keep in mind that groups fired from a completely unsupported position are a poor instrument for gauging mechanical accuracy.
Shots fired/number of shots in the group: Include this information even if you show pictures. It’s not always obvious how many shots hit the target, and certainly not obvious if there are flyers outside the frame of the photo.
Number of groups fired/Average Group Size: If you fire multiple groups, consider all the data as a whole. The smallest group might be the most exciting, but an average of all the groups is a more accurate reflection of the results. A large variance between groups might indicate a problem with either the equipment or the shooter (e.g., poor trigger control, loose optics mount, excess fouling in the bore, etc.)
Keep in mind that for most applications, the above information is the minimum needed in order for the groups to tell you or other shooters anything useful. The longer the distance and the more precise the expectation of accuracy, the greater the number of variables that should be considered. The above data would most likely be sufficient for an application like testing the accuracy of a stock production defensive pistol at 25 yards. A hunter who’s shooting groups to confirm zero on his rifle might need to consider the difference in temperature between the day at the range and the anticipated hunting conditions, or whether the shots were fired from a cold bore. A long distance shooter trying for groups at 1,000-yards would have many more factors to consider that the above list does not even begin to address. The context and application will always determine which variables are most important.
Next week, I’ll revisit this issue to address a few of the specifics of shooting and measuring groups, as well as provide a sample range report following the list above. In the meantime, let us know what kinds of information you look for in an accuracy test.
What method do you use to shoot groups, and what kind of information do you like to see in range reports given by others?