Rifle zero
Where to start? A very, very common question we get at Florida Multigun and the point of endless debates by keyboard warriors is what is perfect zero yardage for the rifle? Even among serious 3 Gunners the topic can be a heated discussion. I’m going to give you my thoughts and some quick math to prove why I think the 200 yard zero is perfect for 3-Gun and a lot of AR applications. You might find another distance that you like but I’ll tell you why I set my rifle up the way that I do.
Is the 200 yard zero the same as the 50 yard zero with an AR? Yes and no. The 50 yard zero and 200 yard zero will line up very, very close on drop charts but I prefer the 200 yard zero as it is a little more accurate. In my experience the 50 yard zero doesn’t account for the accuracy at further distances out to 200+. The 50 yard zero is perfectly acceptable for most rifle uses but for 3-Gun I prefer a longer distance zero. The other reason for the 200 yard zero is the nature of the drop curve between the majority of the distances we encounter at a 3-Gun match and defensive purposes for that matter. Let's look at the data:
Between 0-250 yards with a 200 yard zero we wouldn’t miss the target by any more than 3.5 inches and we would only be 8.7 inches low at 300 yards. At 300 yards, on a full BC silhouette gong, holding around the shoulders we would have an impact. You will be a little high at 100 yards but only by 2 inches which isn’t enough to miss 99% of the targets we put out at Florida Multigun. After 300 yards you will start having to hold over with almost any zero so that’s a wash.
Also, I think 200 yards is a good range for 5.56/.223 before wind and other variables start messing with zeros and group accuracy. Sometimes 200 yards is a long way if the wind is blowing so take that into consideration before heading out to the range. Another selling point for the 200 yard zero is the myriad of scopes that feature Bullet Drop Compensation (BDC) reticles which rely on the 200 yard zero for the function of their reticle and built in hash marks. I’ve had bullet/velocities not line up exactly on 300, 400, etc and I’ve experimented at zeros that fit those BDC reticles but that is outside the purpose of this post. If you need more information on that let me know.
What about other distances like 50, 100 or 300? Again, I think 50 is too close for an actual zero but based on the above data on the 200 yard zero, @ 50 yards bullet impact is only .9 inches high. I will tell you a secret before shooting major travel matches, it’s very important to know where your 50 yard zero is as some matches don’t have access to test out to further ranges (50 yard max) even though you will be required to engage targets much further. So after flying or driving to a match it’s always best to test your equipment and check your rifle zero.
100 yards is a very common zero in a lot of rifle situations. All my precision rifles carry a 100 yard zero but I dial much more on those rifles as I usually require more precise distances and holds.
If we look at the data on the 100 yard zero:
With a 100 yard zero under 150 yards we are doing ok. The bullet path is very flat. At 200 yards though we are already dropping 4 inches and by 300 yards it’s almost 15 inches of drop. 15 inches would be enough to completely miss the target if holding below the head of a large silhouette gong and a full miss on most of the round targets we have at Florida Multigun. Some of our shooters use the 100 yard zero very successfully so there is a good argument for that distance.
300 yard zeros in my opinion are too far for 3-Gun zeros as the trajectory curve at most of the shorter distances is more dynamic. Meaning you would have to manipulate your holds a lot more at the 10-50 yard shots that we more commonly engage paper targets. Those tight no-shoots become much more difficult and you have to do a lot more math on shots that shouldn’t require it. Also the 5.56/.223 caliber and the AR platform is much more difficult to shoot accurately out 300 yards to get that zero established than bolt guns.
Now that I’ve decided on a zero, what do I do when I change rounds between my 55 grain blaster ammo and my more expensive long range ammo? What I have done for years is zero with my long range ammo and use it on shots 250+ yards. Using the long range ammo zero, I shoot a couple of groups at 200 yards and 100 yards with my 55 grain ammo to see where they hit. In my experience, the 55 grain blaster ammo hits within a few inches of my zero so I haven’t had to worry about having two zeros. I will sometimes have to hold a little right on Area 51 on smaller steel plates as my zero is off by 2.5 inches at 120 yards to the left between the two rounds. Closer than 50 yards the two zeros come out in the wash on most shots. Also, not technically a zero issue make sure to brush up on mechanical offset in rifles with larger scopes as the height over bore can be troublesome for tight (< 10 yard) rifle shots on no-shoots.
So, based on all of that information above, pick your zero and learn your holds for your rifle and ammo combination and get out on the range.
Shine
