If you are into shooting at all, you are either reloading already, or you probably will begin to in the future. Particularly in the precision shooting realm, affordable and match grade are terms that do not mesh well. At the time this review was written, Federal Gold Medal Match ammunition, is going for $29.99 per box of 20 rounds. That works out to $1.50 every time you pull the trigger. That’s all fine and well and you can’t take anything away from Federal, they make great ammo. Unfortunately, most of us can’t afford to shoot as often as we want at that price point. So we learn to reload our own ammo. Reloaders are a fickle and superstitious group, always looking for ways to make their ammo a little better, a little more accurate, and a little more consistent. Runout is one issue that can cause issues for the reloader, and Hornady has a solution, the Hornady Concentricity Gauge.
What is runout? Essentially, it’s a lack of consistency in the angles of a loaded cartridge. If you were to draw a line straight down the middle of the case and call that your centerline, the ideally loaded round would have the middle of the base of the bullet, and the tip of the bullet, both lining up on that centerline. Variations in neck thickness, cases with necks that aren’t concentric, play or slop in your reloading press, and a long list of other factors can contribute to a lack of concentricity. With a round that has runout, or a lack of concentricity, you have the bullet pointing a few degrees off of the centerline. How much this little bit of variation really matters to accuracy downrange is the topic of much debate and controversy.
So much so that here at AccuracyTech, we plan to test it and find out. We are going to cherry pick some loaded rounds showing .005 or more of runout and fire a few groups with them to see what kind of effect that has on accuracy. We will then compare it to rounds we have checked and either show runout of .001 or that show more but had the runout corrected using the Hornady Concentricity Gauge.
Why does runout matter? Well, the theory is this, all these little sources of inaccuracy can combine to cause issues with accuracy. With the projectile not concentric with the case and the chamber it creates pressure and tension on the case, yielding inconsistent release of the projectile. This can then lead to inconsistent barrel timing with varying muzzle velocities and less consistency downrange. We plan to test it and see, but in the case of the Hornady Concentricity Gauge, it performs as advertised. It provides a means of measuring and correcting the runout found on hand loaded ammunition.
The main body of the Hornady Concentricity Gauge is cast iron, making for a solid base. There is a shell holder that you can place the base of a loaded round into and there is a hollowed out extension on the other end for the tip of the projectile to rest inside. You can then adjust where the dial caliper meets anything in between. This is especially useful because you can use it to check concentricity of a loaded round, or even a case neck and body. There is a simply pull and pivot lever that tightens or loosens the dial caliper and allows it to float forward and rearward along the rail beneath the shell holder.
Hornady recommends you line the dial caliper up on a specific portion of the projectile for measurement. You then spin the cartridge after zeroing the dial caliper and the gauge will identify any runout present in the cartridge. When you have identified where the bullet is farthest from concentric, there is a small screw with a rubber head that you can dial in to ‘push’ the projectile back towards concentric. It takes some fiddling to work up a system for correcting the runout but once you get the hang of it, the process is quite easy and fairly efficient time wise. You can then correct any runout present in your cartridges with the Hornady Concentricity Gauge so that, ideally, you have very concentric rounds being chambered. I’ve even gone as far as to chamber a few after correcting them (with the firing pin removed from the bolt, of course) to see if merely chambering the rounds was enough to induce runout and perhaps negate the time spent on the process in the first place. I’m happy to say that after trying this several times, I noticed no increase in runout after chambering the round several times from what it was going into the magazine.
The heavy use and high contact areas of the tool are made of appropriate materials, cast iron and aluminum. Durability isn’t a huge issue for a bench tool because we won’t be taking it into the field or to the range and knocking it around. However, nobody likes paying for tools that break or don’t last. That said I don’t see much potential for the Hornady Concentricity Gauge to break or fail unless it is abused in some manner as to cause a failure.
The price on the Hornady Concentricity Gauge puts it right in line with other special purpose tools for the reloading bench. It isn’t a steal of a bargain nor is it anything that would break the bank. Whether or not it is a tool you need to bother with in the first place remains the subject of much discussion and disagreement. Keep checking back to read up on our test of concentric versus non-concentric ammo fired for accuracy.