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Maximum Hangtime: Getting the Most Out of your AR15 Zero

Maximum Hangtime: Getting the Most Out of your AR15 Zero

If you had to rely on one zero, what would it be?

For a long time, the mantra has been that the 50 / 200 yard zero is the most useful zero for the AR15 platform as it offers a flat trajectory for the 5.56 cartridge. It is good advice and I have a few rifles zero’ed for 50 myself, but it’s not the “best zero”. The 50 yard zero is a vanilla standard, as it suits almost everyone well… but each rifle or carbine is a unique combination of barrel length / velocity, bullet weight, and shooter. If each rifle setup is unique, then can we do better than a “vanilla” zero for each rig? Yes.

Many of you might have heard of the maximum point blank range method of zeroing. MPBR is a zero scheme that is unique to your rifle and loading. It maximizes the “point blank range” where you have to remember a single hold to get hits out to the end of the point blank range, hence “maximum point blank range.” As an example, imagine a disk six inches in diameter and I want to hit that disk as far out as possible with one zero. How would I do that? I would zero the rifle so that the trajectory of my bullet will arch 3 inches high and where the bullet would fall 3 inches below my line of sight, that would mark the end of my MPBR zero. That disk could be at 25, 100, 212, or 274.5 yards and a single center hold would allow me to hit it with no need for holdover. 

Hunters have used this method for a while, but with the popularity of the bullet drop reticle, it has fallen by the wayside in recent years. So why not just use the bullet drop marks? Because time. Your target, be it defensive or hunting, will present you with an opportune shot for only a few seconds. Ranging and doping the target, even with a BDC reticle, may not happen fast enough and / or you may miscalculate. That 18 inch shoulder-width ACOG ranging system isn’t so useful if the target is standing sideways or presents only for a split second. We want to put rounds on target, with the highest probability to intersect the target, without having to try and estimate range. Anything inside of my MPBR I want to aim at and hit without worrying about hold over, hold under, or BDC stadia. That’s the beauty of the MPBR method, it allows you to tune your trajectory to tailor suit your rifle, your loading, and your target diameter. So how do we zero with this wunder method?

Let’s start by expanding upon why we want to ditch the 50/200 zero mantra and see how things go with a 3 inch diameter MPBR:

Point. Click. Hit.

You need a ballistic calculator and some load data. I recommend Strelok on the itunes or android store. Strelok has a wonderful tool built in that lets you calculate the maximum point blank range right in the app and is a powerful tool. Let’s proceed with some more examples as to why MPBR is worth the trouble over a standard 50 yard zero.

With a 50 yard zero in a 20 inch rifle, shooting XM193, you can expect a bullet apex (aka maximum ordinate) of flight to be close to 2 inches (by my calculations) and then it falls back to cross your line of sight again at 225 yards. Wait, it’s not over yet. As the bullet continues to fall, it will fall 2 inches below your line of sight at 259 yards. The maximum point blank zero here is 259 yards meaning you should be able to hit a 4 inch disk from 0-259 yards with a dead center hold. Think of the MPBR as the acceptable vertical resolution where the bullet’s trajectory stays inside the defined size of the target.

Now let’s bring it out a new MPBR zero which allows us to stretch that useful range out a bit more. Let’s zero so the maximum ordinate of our XM193 is 3 inches above the line of sight.

mpbr

Anything inside of my MPBR is in the danger zone with no need to hold over. This zero is actually a 264 yard zero which gives us a 3 inch rise and a 3 inch fall at 300 which marks the end of our MPBR. How do we zero at 264 yards? Use a ballistic calculator app such as Strelok!

So if I am shooting a 20 inch AR15 with XM193 and a maximum bullet rise of 3 inches over my line of sight, then I just extended my MPBR to 300 yards where at that point the bullet would dip 3 inches below the line of sight. That has effectively changed our “resolution” to 6 inches where the bullet would stay in the defined target zone. A 6 inch resolution easily fits in the space occupied by a human head out to 300 yards! That means a dead hold to the middle of the face will potentially score head-shots out to darn near 300 yards!

Remember, this sighting method is target size defined and shooter-rifle-projectile unique. Each rifle and loading will need to be entered in Strelok (or other ballistic calculator) to determine the best zero for your desired target diameter. Why does this apply to a defensive rifle / carbine? In a self defense setup, we need to maximize the distance where we will hit our target *without* shot correction.

If the target is inside our point blank range… we want the rifle to be a simple “point and click” interface. Bam. Hit. We want the highest probability of hitting a head, torso, or half exposed limb. Point. Click. Hit. We want to maximize bullet “hang time” to increase the probability our projectile will hit the target at unknown distances. Click. Boom. Hit. So why not 4.5 inches up and down if the average head is 9 inches tall for a MPBR of 349 yards!? Why not a 3.5 inch zero for a 7 inch diameter vital zone!? Sure, you can do that. It’s all up to you and it all depends on your expectations of precision vs the diameter of the target.

Remember that standard zero’s are made for shooter convenience and not what’s best for your rifle and projectile combo.  Ranges come in known distance increments and we pick a set distance to zero out of convenience. That 50 or 100 yard zero for your setup doesn’t stretch out the rifle or carbines maximum useful trajectory. So what should be our goal when we zero?

Goal: increase the probability that the projectile will intersect the target *without* calculations.

Factors: Rifle and bullet accuracy, shooter accuracy, target size, and environment.

A defensive target, once engaged, will not stand up waiting to be shot. They will be hiding, returning fire, and they will present a small target for the shooter. Three inches of rise and fall (for a total of 6 inches of vital zone) gives us a great starting point for hitting hiding, peeking, or partially exposed targets. So instead of estimating range in a quick, violent engagement, I want to hold dead on and know that if my target is inside of 300 yards, that target is gonna get hit. This simplify’s ranging immensely. No holdovers. No hold unders either. My only quesiton “is the target inside of 300 yards?” Yes? Then just a dead hold. 

DI Optical FC-1

Red dots would be of benefit for this methodology behind a “perfect” zero. Add a magnifier and you can hit targets near and far with two holds.

Six inches of total vertical resolution seems like a logical choice for a MPBR setup and extends us past our 50 yard / 200 yard zero a bit and is still a fine resolution for engaging defensive targets. I can’t think of anything I would shoot at that would be missed because my trajectory apex is three inches high. Look at your knee. It likely has a targetable area of at least six inches. Torso? This 6 inch resolution is easily inside the vital zone of a center of mass hold.

So next I whipped up a basic chart to get an idea of what zero at 100 yards I would need to get a MPBR which targets a 6 inch radius.

XM193 and Mk 262: Sight in at 100 yards X inches high in blue for a bullet apex of 3 inches; the MPBR is in red for each barrel and projectile. The XM855 would benefit at similar zeros as it will be in between the MPBR of the 77 grain and 55 grain ammo.





Barrel Length10.514.5161820
xm1932.62.42.52.2
2.0
MPBR262281289300303
Mk 2622.82.62.62.52.4
MPBR242261270279284

 

So you can see there is a bit of difference in the MPBR between rifle, carbine, and bullet. At one end we have the longer point blank range of the 55 grain XM193 and at the other end the heavier 77 Mk 262 at the other. With modern ballistic calculators such as Strelok, you can simply zero at 100 yards, input the maximum target diameter, take the recommended zero for your new MPBR and Strelok will tell you how many clicks up from 100 yards to achieve that zero goal.

This method of sighting in gives you some excellent hit probability. If the target is near, a dead hold will hit anything in your maximum point blank range. If you estimate the target is at 300-400 yards, holding on the head will ensure rounds drop into the mid torso. If you were incorrect and your target was closer than you estimated, your projectile would still likely hit the head.

It appears that M193 or, even better, a quality defensive 5.56 equivalent such as Hornady 55gr TAP would make the best choice because of the high velocity achieved by 55 grain loadings… but when wind is thrown into the equation the 55 grain stuff makes it more difficult to hit the small targets at the end of its MPBR. So let’s look at heavier match bullets, what benefit do they offer? Increased accuracy and increased wind resistance.

Adding the Variables; wind, accuracy, and MPBR

Typically M193 is considered a 1.5 to 2 MOA load and the 77 grain Mk 262 is considered a sub MOA load. Think of each bullet as a probability to hit an area based on its accuracy. Groupings are the defining measure of whether a MPBR zero will be effective as inaccurate ammo could possibly land too far away from our target radius to remain useful. If your gun cannot keep groups inside the defined zone, then the distance you have chosen won’t work very well since trying to keep the bullets in a 6 inch diameter target zone out to 300 yards wont work if your rifle is shooting 4 inch groupings at 100 as an exaggerated example.

Ideally you should start with a accurate, free floated barrel, and use the best ammunition available to you. In our exaggerated example of a rifle shooting terrible groups of 4 inches at 100, consider that at 200 the groupings would double to 8 inches, and at 300 the groupings would run around 12 inches. This eliminates the gains of our MPBR since many of these shots will escape our defined target zone due to simple inaccuracy. A match projectile on the other hand, which shoots 1 inch or less at 100 yards, 2 inches at 200, and 3 inches at 300 will remain useful inside our maximum point blank range.

mpbr-ar15-maximum-point-blank

With an accurate projectile, we can keep our groupings relatively close to our 6 inch diameter target zone. On the left the accurate projectile strays outside the targetable zone at its maximum ordinate and at the end of the MPBR, but still remains tight and effective. On the right, an inaccurate projectile could possibly throw rounds far outside our targetable zone and this could result in more misses.

Wind can cause us horizontal shift away from our intended goal of hitting the target. With our example of a 6 inch diameter target and a MPBR of 300 yards, I still want to be able to hit the target in a slight wind. The benefits of match ammo are two fold: better wind resistance and tighter groupings. Both of these characteristics are just what we want when setting up our rifle or carbine. In the 20 inch gun, the Mk262 gives us a MPBR for our six inch diameter target of 284 yards which sacrifices 16 yards from XM193… but the gains in accuracy and wind deflection make it the logical choice for a shooter who wants statistically significant gains on hit probability. As long as you do your part and shoot well, the higher accuracy and better wind resistance will reduce flyers which could land outside our intended target.

Wrapping Up:

So ultimately, your shooting goals should play into the rifle and its associated setup and upgrades. A red dot or BUIS set up with a MPBR zero will assist you in hitting targets of opportunity and at any distance inside your MPBR “box”. Since we cannot effectively range estimate every shot on fleeting targets, best practice would be to utilize MPBR to ensure hits by maximizing projectile trajectory as it relates to the size of our target. This method may be off-putting to those with a ACOG or similar rifle optic since it negates the benefit of the bullet drop stadia. We don’t need no BDC stadia to be riflemen. We need knowledge and best practice methodology to ensure hits at any distance.

Best practice appears to be a heavy match bullet out of a rifle length platform to maximize the flat trajectory of the projectile and to take advantage of better accuracy and wind deflection. This should increase your success in hitting targets without much correction.

20-inch-556-dmr-cmv-barrel-1

If wringing out every last advantage you can get is your game, the 20 inch barrel is what you seek. Shown above a 20 inch rifle length Ballistic Advantage DMR in 5.56

The true value of this setup is that it helps free you from thinking about your target distance in hundreds of yard incrrements, and instead it allows you to estimate either near or far. Is the target inside of my MPBR? Yes? Point. Click. Hit.

Integrating this into my setup… I foresee finalizing my optic equipped rifle with two loadings: XM193 for practice, and Hornady 75 gr HPBT for longer range work. The Hornady is considerably cheaper than the 69 grain SMK I have been shooting, and switching back and forth between the two loadings is as simple as uncapping the dial and rotating in a few clicks of elevation and wind-age. I think these loadings can cover all shooting I can ever realistically do. I really like this method as it increases the probability of intersecting the target at x range inside my MPBR zone. It’s important to get away from the 100-200-300 yard paradigm and examine a zero which allows a more fluid approach to hitting a target at unknown ranges… because remember this, if nothing else; every target will present at an unknown range.

The goal of a marksman is to study the platform and integrate the best practice findings into his or her shooting. I think it is safe to say that for work inside of a MPBR of 300 yards, the 77 grain Mk 262 offers the best probability of hitting the target if shot out of a rifle length system, and its excellent characteristics make it best for environmental conditions. XM193 makes a good substitute as your holds would be the same, but wind may knock you off target without some very light wind correction.

 

Written by lothaen

39 Comments

  1. honeycomb · July 15, 2015

    Interesting. But, you aren’t to far removed from th 50/200 yard zero method of before (re: chest, head, hat).

    Considering ammo moa is good but you should also understand that most red dots are 2 to 4 moa. I have a 1 moa EoTech but I still use the 50/200 yard zero with it. If I am running a scope with a mil or moa etched reticle (i.e. precision rig) I zero at 100 meters and dope from there.

    If you run a duplex scope (e.g. hunting) then this is fine. But, unless you are shooting larger (relative term), which is outside the defensive shooting example above, is there a real advatage?

    It’s good work on your part. But, in a defensive encounter, would you be shooting anyone (i.e. be justified) beyond 150? To you and me in a court of law I could bring myself to believe it’s possible. But would your (non-gun) peer’s?

    This may be a great 3g set-up though. I might like it better than my tried and true 50/200 zero.

    Enjoy your vacation.

    • Shawn · July 15, 2015

      as Honeycomb said above. all this is nicely over thought out, but marginally useful over a 200 yard zero. a few other points, is what a aiming point will equal out to cover at range. ie. some cross hairs o, irons or dot may cover 4 inch at X range,.. thats not much “wiggle room” I would also be interested how you would justify a 270 yard shot in a self defense situation. furthermore. where you got info that M193 is considered 1.5 MOA accurate I have no idea. maybe that is a typo? cause otherwise that is pretty far fetched. especially since 193 quality is highly variable. and even if it was not, I would never recommend it for any serious purpose especially if I needed something with better terminal performance for self defense.
      with a reticle with that is set up for long range shooting, your method was be of no value.
      hunters have used this method for a long time until better and flatter rounds came out.and it works OK on larger game, but its not really much of an improvement over other methods

      you are about to fall into a common trap in your thinking about how to do something faster and easier

      • lothaen · July 15, 2015

        As everyone said its very unlikely for anyone of us to shoot past 25 yards in a self defense situation, but its all academic since I will most likely have my pistol if a self defense situation arises.

        Since I want to push the rifles out far, why not study methods that are likely to help me hit targets with a simplified method?

        I think of my rifle as a sliding scale. Up close I need to focus on speed on target with simplified techniques that maxmize the potential to get rounds on target… At the other end, the 400-700 yard line would be a focus on precision and the methods long studied by Rifleman like yourself.

        It doesn’t improve too much on the traditional zero’s, but if it creates a change which makes it harder to miss my mark, I want to try it.

        If it sucks, then I guess I’ll ditch it. 🙂

        • Jwedel1231 · July 16, 2015

          Here’s how I see it:

          The MPBR method you outlined above has been used by hunters for decades because they had scopes with crosshairs and no dots or BDCs. They were slower than irons, but more precise. We now have better reticles that are even slower to use than duplex reticles, but much more precise. We have not made anything better or worse, just allowed us to trade speed for precision to a higher degree. In close, precision is not that big of an issue compared to speed, and the reverse is true at distance, which is why pistols have iron sights (and sometimes red dots) and long range rifles have scopes.

          My point is that you are going to what seems to be an older method of aiming that favors speed over precision, though maybe not by much.

          I personally lean more towards precision over speed, so I will probably stick to 50/200 zero, and compensate bullet drop beyond. What you do is your business, but we do enjoy reading about it. 🙂

    • lothaen · July 15, 2015

      You and Shawn below make some good points regarding the reticle size. Right now I run a Razor which has 1/2 minute crosshairs, but other shooters may not run the same so you guys are right the reticle needs to be considered in this sighting method.

      As multiple people have pointed out I am overly generous with the accuracy of M193. One of the most accurate of the M193 rounds appears to isreali IMI and that can squeak in at roughly the 1.5 MOA with a match barrel as shown by MOLON in his M193 test.

      It’s not too hard to increase the diameter of the 1.5 MOA reference in your minds eye and you can see a slightly larger diameter of the accuracy circle representation can really put you off target quickly.

      Absolutely respect everyone of you guys who can shoot and have been doing this a long time. I understand some people won’t see the value of this method and a extra few yards… But if I were a statistician I would be interested in the probability of the bullet and the potential for increased hits via best practice methods for hitting a target at unkown distances.

      As for the self defense… It’s all ridiculous until we see the reality behind the curtain. Remember the curtain will fall at some point and then we will be grateful for what we learned or passed on to our kids. Behind the curtain is the true monstrosity that is unchained and unhinged man. We have a sneak peek behind the curtain right now in the Middle East.

      My rifle is being set up for the worst case scenario.

  2. honeycomb · July 16, 2015

    Keep it up lothaen (re: blog). I rarely post .. but stop every so often.

    A nation of riflemen would be a great outcome. I’m 45 years old and grew up in a firearms family. It wasn’t till I joined the military after college I realized not everyone did .. in fact very few did.

    Those golden years may never return .. but it won’t be from a lack of your effort.

    Cheers

  3. honeycomb · July 16, 2015

    BTW on the M193 moa issue .. I always thought / recall it was a 2.5-3 moa round.

    It wasn’t until the M855 contract that we (i.e. the US Governement) demanded better.

    Of course I could have remembered all that wrong. In which case disregard.

  4. DAN III · July 16, 2015

    What about the USMC’s 36m/300m zero ? It is my understanding that this zero allows for the least amount of holdover when using the M855/62 grain Green Tip.

    Myself, with a 14.7″ barreled, 5.56mm I’m using a 100 yard zero with a GRSC 1-6x scope. I am having no issues consistently hitting the combat effective zone at 300 yards.

    • lothaen · July 16, 2015

      There is definitely more than one way to skin a cat, and for s long time I used a 50 yard zero for carbine competitions etc. I even had good luck on moving targets at 300-400 yards with that zero as we used to hold up targets on sticks and walk them through the rifle pit while those on the firing line got to shoot at the movers.

      I think my interest is “will best practice methods permit me any statistically significant changes in hit ratios”?

      Obviously I have no way to fully test that without a study, but with modern ballistic tools I was able to measure and examine wind drift, accuracy, and bullet drop and Overlay them on a b27 to see which zero and setup would keep me in the target zone the longest and resist accuracy issues and environmental factors.

    • Jwedel1231 · July 16, 2015

      I think the MPBR method, and the 50/200 zero (or 36/300) style of zeroing are most effective in red dots and irons. When using magnification, I believe that a 100 yd zero is best since you have the ability to either hold over or dial. As always, everyone is an individual and what works for most never works for everyone.

  5. Colorado Pete · July 16, 2015

    Good article. The value of PBZ as you say is to reduce the amount of thinking by the shooter in a stress situation, by maximizing the distance within which one doesn’t have to apply elevation correction. One decision – is the target with my MPBR or not? If so, hold center and shoot. If not, then do what correction work is necessary.
    Having a sharp eyeball judgment for your MPBR makes it all come together. Works well for field shooting, either hunting or battle. And still works even with higher velocity hunting rounds, or varying target sizes; the method doesn’t care how fast or slow your bullet is, or how big/small the target. In the field there are no even-hundred-yard markers.
    Having to make only one decision under stress usually beats having to make more.

  6. Chad Shearer · July 23, 2015

    This seems incredibly well thought out and well written. However, and this is going to ruffle feathers as there are some absolutely accepted terms in this community, I quickly lose faith in any expert that uses the term “bullet rise” and believes in it. Again, I know it is common and accepted as truth, but it defies the laws of physics, and if I could draw a picture and upload here to help explain it, I would. Any expert that uses this term concerns me as to what else they don’t understand.

    • lothaen · July 23, 2015

      Would common people reading this article understand “maximum ordinate” without simple explanations?

      I use simple terms that I think would help people understand the concepts, even if they aren’t the ” correct” terms. The blog is written for everyone who wants to pursue marksmanship and not just for enthusiasts. I particularly think its important to help the newbies and people curious about getting into marksmanship.

      Thanks for the compliments. I hope it is well written and expands on the concepts well. I am going to trial the method here soon and see how well it works. After all, its only three clicks up from my zero. If it doesn’t work, I go back three clicks down. 🙂

    • Dave · August 30, 2015

      But…the bullet does rise? Because (if the sights are zeroed at all) the muzzle has some upward cant, so you’re shooting upwards a bit? No physics defying here, just basic ballistics.

  7. Todd Scheck · July 23, 2015

    So this is subjective to the ammo you use, but, not completely a perfect method. With that, the military continues to train the 25 / 250 zero method. How does this train of thought match those who’ve already trained this way for so long, like myself a 12yr veteran, US Army Infantry?

    • lothaen · July 23, 2015

      Just an alternative I would think. No doubt there are multiple ways to skin the cat, and a master of one method can outshoot the novice of another valid method, but I have been seeking simplified methods that reduce holds and increase (however slight) the chance to hit a target at unkown ranges under duress of time.

      What methods can we use to ensure best practice? What ammo and sighting method gives us the highest probability of intersecting the target in spite of environmental conditions and shooter error? Etc.

      If i Had the opportunity to study rifle methods and check hit ratios in a controlled setting I would jump at the chance, but for now this seems as close as I can get to best practice methods with my current AR15 rifle setup. Everyone’s mileage may vary with different setups.

  8. lothaen · July 23, 2015

    Oh one thing guys, where is this being shared on facebook? Your blowing up my server. THANKS FOR VISITING!

    I appreciate everyone stopping by!

  9. Lindsey Bertomen · July 23, 2015

    First,
    This is a well written, well conceived article. The topic definitely should encourage users to couple their cartridge/firearm combination with the actual application.

  10. Don Mcmahan · July 23, 2015

    also depends on how hi above the bore the sight is

  11. Spc. Wayne · July 23, 2015

    It might help if one were to use meters instead of yards, which are in fact different from each other. It would avoid a person getting confused at the use of terminology when they likely learned to zero using meters, as is the convention in the military to do. Plus, I do think you’ll be hard pressed to find AR15 sites set up in yards instead of meters, so if you are behind an AR15 and you’re using yards, you’re setting yourself up for failure from the start.

    • Ken · November 5, 2015

      Meters and yards are so close to each other that i consider both the same. i do not notice any displacement on this issue as far as putting holes on the target.

  12. George · July 23, 2015

    I kinda glossed over the comments but as I see it, we have to define the distance we expect to engage targets long before we have a discussion about zeroing and maximum engagement distances. As a police officer in a mainly urban setting, my likely engagement distance ranges from contact distance to not much more than 50m with the average distance being well under 25m.

    Under these constraints, I have no need for a 50/200 or anything approaching that kind of zero. What I really need is a zero that works for close, precision shots without worrying too much about offset up close. I found that between a 15 to 25m zero was good for this but put me way off at 100 for qualification. (don’t even get me started on why urban LE qualify at 100m….. ) I resolved this by using my iron sights set on a 50/200 setting with my red dot on about 15m zero. Seems to work reasonably well.

    For my other AR’s I just simply zero at 100m and either dial or hold over as required.

    • 10-32 Solutions · July 24, 2015

      George, you are not seeing forest through the trees with your comment, and that mentality is why we have supervisors that try and tell us to zero at 7 yards for entry work.

      #1, there are plenty of locations where I can see 100 yard+ shots. An aisle in a Walmart. Quite a few school hallways Quite a few parking lots. Industrial areas. I can also envision and justify numerous uses of deadly force out to 400 yards, although lesser in frequency. There have been LEO shooting incidents at extended distances.

      #2, Choosing your zero only by looking at what distance you are going to use primarily, such as only shooting threats at 25 or 50 yards, and choosing to zero accordingly, fails to take into account the whole concept of keeping a shooting trajectory flat and easy to use, because it only focuses on the close half (Also completely forgetting about height over bore sight considerations as well.), and complicates matters when the LEO is called upon to quickly know where the bullet will impact at distances beyond those common ones.

      It’s not about what is the most common. It is about what is the most efficient.

  13. 10-32 Solutions · July 24, 2015

    I am not a fan of increasing the size of the target area in order to increase the distance one can use a point blank zero concept. Under stress, our accuracy already will suffer. One can expect group sizes to double. Add to that the 2-4 MOA group size that can vary with ammunition quality control. And now you’re adding an increase in the acceptable size of the target area. Looks very good on paper, but you’re helping to stack the deck against the shooter under stress.

    You’re also basing data on a 20-in barreled rifle. Many many more shooters own and use 16-in or less barreled AR/M platform carbines for defensive purposes than they do rifles.

    The acceptable COM is considered to be an 8-in circle. A standard of being able to hit 4 out of five shots in a 2-in circle at 50 yards transcribes to 4 out of 5 on a 4-in circle at 100. Which means under stress, 4 out of 5 hits on an 8-in center of mass at 100 yards under stress.

    The 50/200 zero variations and the 100 yard zero work well because they have been tested and had various bugs worked out. Concepts such as what you’re promoting are akin to the military 25/300 zeros that allow for a person to miss head shots as close as 100 yards because of the higher allowed maximum ordinate. It’s taking people backwards.

    It already is simple to use a 50/200 variation for defensive use. Point of aim/point of impact out to 200-225 yards, depending on ammunition and barrel length. 300 yards, aim for the head for a COM hit. 400 yards, aim a head high for a COM hit. Works with 2MOA and 4MOA dots, and can also be applied with magnified optics.

    • lothaen · July 24, 2015

      Thanks for your input. The method of hitting a target with the red dot of chest, head, and “knock of the hat” is very simple, and works well. The question is can we improve hit probability with best practice methods? What type of bullet drifts the least? What type of zero will hang in the kill zone the longest? What barrel length would be best for the task at hand? Light and fast match bullet, or slow and heavy match bullet? Etc.

      I based the data on what I would consider best practice. Best practice would be the highest velocity you could reasonably attain for a heavy match bullet which combats light wind. The use of a match bullet would permit more wiggle room for shooter error. Would 2 inches of rise instead of 1.5 or 1 inch at x range cause a miss? If you had a bit of error and let the shot loose another inch high would 3 inches of rise miss a head-shot? If the average human head is 9 inches x 7 inches + or – an inch. So you are dealing with 4-4.5 inches of rise *OR* fall where your shot will land inside the head.

      If there were a way to take two groups of shooters and compare hit percentages with traditional zeros and associated shooting theory vs those trained in MPBR methods then that would be the bees knees, but I lack the resources to do such a study. Ergo my challenge is to take this method and apply it in the competition world and see how it works out.

      • 10-32 Solutions · July 24, 2015

        In order to improve it, what have you identified as not working as efficiently with current proven methods?

        Is it best to use a heavy match bullet, or one that has better terminal performance, and thus more likely to be used for defensive purposes? You stated that your intent was to improve defensive use, therefore it would make sense to use loads or bullets that supported that. Match bullets and/or the heavier bullets on the spectrum are often not the best defensive choices, as shown from data on shooting incidents or scientific testing in media.

        The maximum height of a 50/200 variant can be between 1.5 inches on paper to 2.5 inches. Your MPBR theory is doubling that to 4-4.5 inches of height based on the size of the human head. Are you basing this on just the size of the human head, or the size of the actual target zones required for terminal performance? There is a reason head targets have a 4-in brain zone, and not a 7-9 inch one. Also something you aren’t considering.

        • lothaen · July 24, 2015

          Just a quick anecdote on match ammo performance: multiple tests have shown that open tipped match bullets such as the 77 gr and 75 gr jacketed match ammo perform well in a defensive role and show substantial fragmentation: 75gr test and 77gr test.

          If the links are broken forgive me I will fix them when I get home.

          As far as hitting the terminal zone itself, what’s to say that, at a unkown range, you might estimate the distance incorrectly and you drop rounds too low? How do you quickly range a head when most stadia aren’t set up for a 9 inch diameter target? I think, again in theory, that using the MPBR method would likely put you in the terminal zone as often as other zero’s particularly if our target is at a unknown distance.

          Thanks for the continued discussion. Nothing here invalidates proven methods, so I want everyone to know that… But if we had to way to examine best evidence, I think some of this MPBR theory might hold some decent water. 🙂

          • Colorado Pete · August 12, 2015

            MPBR is more than a theory, it’s as old as the hills, and it works well, provided you apply it correctly to to the problem you are trying to solve.

            Applying it incorrectly can lead to the issues brought up above. But that is not the fault of the concept, rather the applier. And one of the reasons the Army trains troops as it does, is because they have other considerations, like: how much time do they have to train, and what works best for the average troop to apply without asking too much of him, how “soldier proof” the idea is, and how quick/easy it is for the trainers to get troops up to the minimum desired skill levels.

            I have wondered how many enemy heads showing above a rock have been missed by a soldier aiming center at maximum ordinate range, only to have the round go over the top due to a 300 m zero…a good reason to have your MPBR set carefully.

    • Dave · August 30, 2015

      Knocking the MPBR concept because the military’s 25/300 method is insufficient is missing the point. The article defined the acceptable elevation dispersion as about +/-2″ for relatively small targets of opportunity, with maybe a little room for shooter error built in, then set the zero to maximize the range for that target zone.

      Having a MPBR set up that maxes out at 270y (that means ~2″ low at 270), is VERY different from having a far zero of 300m. He’s not taking a step back, but at least a little one forward.

  14. Karl B · July 25, 2015

    I was in the Marine Corps from ’86 to ’90. Back then we zeroed in at 900 inches or 25 yards. The grouping was 1.2 inches lower than the point of aim. It is still what I use today on my AR platform with carrying handle and built in sights. According to the notes I have written in my USMC marksman notebook I still have today the below info is supposed to be what you end up with…

    Range (yds)……Distance above or below the Line of Sight (inches)
    muzzle…………………..- 2.5
    25………………………….- 1.2
    50…………………………..- 0.2
    75………………………….+ 0.6
    100…………………………+ 1.0
    125…………………………+ 1.1
    150…………………………+ 0.9
    175…………………………+ 0.3
    200………………………….- 0.7

    • RC Vic Kerman · July 25, 2015

      Would be nice to add the Barrel Length, Rifling, Caliber and Grain of the slug. Just curious! Thanks, RCV

      • lothaen · July 28, 2015

        Are you asking what combo?

        I believe a .223 75-77 gr load from a 18-20 inch barrel out of 1/7 or 1/8 twist would be optimal.

        • 1032solutions · July 28, 2015

          Optimal for who? More people shoot 14.5-16 for defensive uses for a reason. 18-20 is more for a 3 – gunner that doesn’t use it indoors or from a vehicle.

          • lothaen · July 28, 2015

            The key is, get the longest barrel accplicable to your needs. If you clear phone booths and regularly hop out of a car at arms, then choose the appropriate arm.

            Since the majority of civilians rely on a concealed pistol as our first line of defense when exiting our vehicle… The rifle is reserved for when things go sideways.

            Once I added a telestock on my 20, I realized it changed the 20 from cumbersome to much improved in the maneuverability dept. Cutting down to 18 keeps my velocity near peak cartridge effeciency and allows me to pick from several muzzle devices and still stay under 20 inches.

            It’s easily maneuverable in my home and I don’t have a problem with it.

            More velocity always helps, it never hurts. Balance that with your portability needs. I recognize that some people do need compact rifles, but the majority of ARs in America are in civilan hands. Not quite the room clearing, pop out of your car with an AR populace that we seem to discuss online.

    • Dave · November 6, 2015

      Those values match pretty close to a 50yd zero, not a 25. They’re 1.2″ low at 25.

  15. Rick · August 6, 2015

    Hey lothaen if you could help me better understand your method since I agree with the POU behind the method for a AR15 specifically setup for 0-300 yard engagements (the exact POU i’m trying to maximize for my AR15) If I was using my 16″ Match grade Noveske AR15 using 69 SMK (only match ammo I have) according to your information I would zero at 100 yards with 1.7 inch high. However help understand if I missed where do you exactly aim at? dead hold center mass? dead hold at the head? and then shoot a group 1.7 inch high approx. from that dead hold? little details like this help noobies like me when we actually go to the range and start to try and put this to practice.

    Thanks

    • lothaen · August 7, 2015

      That’s correct. I don’t know if your optic allows 1/2 minutes or 1/4 minutes, or perhaps its in MILS, but get as close as you can to a click.

      Two holds should cover the zero: Dead hold on the head should deliver rounds to the head out to around 200+ yards and as the distance increases the dead center hold on the head will drop rounds into the upper chest at 300 and lower abdomen at 400 yards.

      The other hold is the chest (center of mass).

      The idea behind the zero is that it maximum bullet rise will never be above your target provided you are aiming at the nose, for example. The maximum bullet arch should no more than 2 inches high above the point of aim.

      That’s tight enough to allow some wiggle room with the hold should you aim a little too high on the head.

      So in use, if you are unsure of target distance, hold for the head. It will cover your shooting out to 400 yards. If they are too close… well then you likely got a head-shot. Shooting center of mass to the chest will also keep you well inside the vital zone.

      The use of match ammo and a match barrel will reduce the influence of bullet inaccuracy in the equation so that’s why it seems to be the “best practice.” The heavy match ammo will also fight the wind to keep you from getting pushed off the head or chest from a light 5mph wind.

      Again, i am experimenting with the zero myself… but this variation of maximum point blank range should really help shooters get the most out of their rifle and projectile combo.

  16. Dave · August 30, 2015

    I’d like to offer some counterpoint to the early comments that MPBR techniques are outmoded by quality reticle systems. With any kind of Mil/MOA scale reticle, your initial zero does not affect the usefulness of that scale, except in terms of the maximum range that the reticle subtends. The commenters appear to understand how this works with a 100yd zero. They appear not to have considered that simply inputting a new zero range (be it the common 50y/200m, or something like 237y or whatever Lothaen’s new far zero works out to be) into the ballistic calculator will give you new range/drop values for each of your 1 or .5 Mil/MOA hash marks.

    Using a system like this with a scale reticle appears to me to be the best of both worlds. If the target is near: point and click. If the target is far (as in too far to make out details of clothing/equipment with the naked eye, and 270yds is pretty close to that limit), then odds are I have time to range his cover and glance at a dope chart taped beside my nose. If the the shot is both far and time critical, I’m estimating and holding, similar the knock the hat technique. Success in any of this will depend on training.

    My caveat: if I had a BDC reticle like Lothaen instead of a scale reticle, I’d probably zero so that my trajectory matched the reticle as much as possible. I’ve seen that work out to useful holds with 200y zeros as well as 100s, depending on the scope and load – whatever gets you closest to big round numbers. You can certainly run the math and print out a dope card with a MPBR zero, but with BDC, I’d want to keep it as simple as possible.

    Great article. Great thought process. Keep up the good work.

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