Understanding Maximum Point Blank Range - Inside MDT

Posted by P.E. Fitch on 2024 Sep 5th

Understanding Maximum Point Blank Range - Inside MDT

Understanding the concept of maximum point-blank range should be a priority for rifle shooters once they're done grasping the fundamentals of position, sight picture, breath control, proper trigger pull, follow-through, and rifle zero. You can think of maximum point blank range as a "special" type of zero that's indispensable, especially when taking quick shots within a certain [known] distance. The concept of MPBR really shines when time is of the essence, and you don't have time to get an exact distance, dial, or hold for a shot.

THE TUNNEL METAPHOR

A rifle's maximum point blank range is the furthest point away from the muzzle, where a rifle's bullet will impact within a specified cone of fire without the shooter needing to dial, hold, or otherwise adjust their point of aim. It's quite simple, and perhaps a good way to visualize is to imagine a tunnel that's a couple hundred yards long.

One end of the tunnel has a rifle's muzzle, and the other has a circular target that's perfectly flush with the diameter of the tunnel. Furthermore, this tunnel's length and diameter are such that the rifle may fire a shot from its perfectly centered position without worrying about the bullet accidentally striking any of the edges of said tunnel. Each bullet fired through the tunnel will always strike the target anywhere on the same area that's concentrically exposed to the tunnel.

A great video from Mountains, Mullets, Merica! discussing Max Point Blank Range and how it differs from a Battle Zero.

Beyond that, these tunnels are completely situational. Their beauty is that a shooter can build a different tunnel for every type of rifle, target, and shooting situation they may find themselves in. It applies as much to the tactical shooter as it does to the competitor or the hunter. Because our "tunnels" can vary in diameter and length, it's also important to keep in mind that a rifle's maximum point blank range is highly situational, and it depends on various factors such as the cartridge, the specific bullet's ballistic coefficient, and its muzzle velocity. Environmental conditions and the actual target (or game) that the rifle shooter or hunter plans to shoot at also play a large role. The faster a rifle pushes out a bullet, the longer its tunnel can be, thanks to the bullet's "flatter" trajectory. The opposite is also true for slower, less efficient cartridges.

BUILDING A MAX POINT BLANK RANGE TUNNEL

Let's build a tunnel for my 16-inch 5.56mm AR-15 shooting a 5.56mm NATO 55-grain M193 round. For simplicity's sake, our target will be a 12x18-inch IPSC B/C steel target that's commonly found in most rifle ranges. Ignoring the lower-percentage head portion, we'll focus squarely on the central part of the target. We could establish a 10-inch "cone of fire" over the target, which would technically work, but that 10-inch width leaves us with very little margin on the sides of the target, which would increase the chance of missing lateral shots. It's important to keep in mind the rifle's dispersion, windage, parallax, shooter's ability, etc., when establishing a reasonable cone of fire for that rifle. If we were shooting at game, any experienced hunter would mention that leaving extra "wiggle room" is a good idea in order to play it safe and ensure ethical shots.

Author's rifle used for testing.

Moreover, I know the 55-grain bulk ammo prints an honest 3 MOA 20-round group at 100 yards through this carbine, so shrinking the impact cone only helps me to avoid misses that could happen even if I fire each shot correctly. So, considering all of these factors, let's choose an 8-inch cone of fire with a 4-inch radius. The 8-inch cone of fire gives me a generous 2-inch margin laterally and more than enough space vertically; it's quite safe for our 12x18-inch B/C steel target. After determining this customized targeting zone for the carbine and target, we want to avoid shots that land anywhere outside the 4-inch radius stemming from the center of the target–the same point where the crosshairs will aim at every time.

The next part in establishing MPBR involves gathering some information, which I already have.

  • Muzzle Velocity: 3100 fps
  • Ballistic Coefficient: .243 (G1)
  • Projectile Weight: 55 grains
  • Sight Height Over Bore: 2.7 in
  • Atmospheric Details For The Shooting Area*

With data in hand, the next step is accessing a ballistic calculator. I use the calculator function on the Hornady app on my phone, which allows users to access most basic features for free. Online or on your phone, this process involves plugging in a range of different zeroes and generating charts for each one while eliminating everything that rises above or below 4-inches. Quite frankly, this is extremely tedious and may be confusing. I found the best way to do this is to visit this website and plug in data directly. I'll confess that I actually "found" my max point-blank range this way, using the ballistic calculator on the Hornady app on my before trying that site and cross-referencing its numbers.

Once the site's built-in generator spits out the numbers (or you find them in your own charts), the idea is to take the rifle to the 100-yard firing line and shoot a solid group that corresponds with the "far zero." In my case, we know this zero lies somewhere between 280 and 282 yards, and even if I don't have access to a 300-yard berm, I can mathematically corroborate this far zero by ensuring that my shots print precisely 2.8 inches high over my point of aim at 100-yards. Similarly, I could even verify this information by shooting a group at 40 yards or my close zero. However, it's always best to verify rifle fire at true distances whenever possible to account for reality.

Maximum Point Blank Range is a great tool for hunters.

Because the Leupold Mk5 on my carbine was already zeroed for 100-yards, the calculator/chart I made on the Hornady app prior to finding MPBR tells me to dial up 0.8 mils so that my trajectory corresponds with the 40/282-yard zeros. But suppose I had switched to a different scope that wasn't zeroed to the carbine–no problem. Simply start by adjusting the scope to the near-zero. Then verify the "inches-over" at 100 yards (and, if possible, also verify by shooting at the other limit of the max point blank zero). With the scope properly adjusted for maximum point blank range, we have the ability to shoot at the B/C-steel target and guarantee that by aiming at the same spot, all rounds will land within an 8-inch zone over the target from 0 to 327 yards.

Building a tunnel for each rifle works exactly the same way. First, determine the best cone of fire for your target, then gather data and input it to that website or your own calculator, and finally, verify with live fire.

TUNNEL LENGTH AND BALLISTIC EFFICIENCY

Let's build one more MPBR tunnel for the same target but with a rimfire Tikka T1X MTR rifle shooting 40-grain .22 LR target cartridges instead of an AR-15 shooting M193 ammo.

Tikka T1X MTR Data:

  • Muzzle Velocity: 1074 fps
  • Ballistic Coefficient: .140 (G1)
  • Projectile Weight: 40 grains
  • Sight Height Over Bore: 2.2 in
  • Atmospheric Details*

Notice how much shorter the tunnel is for a slower and less ballistically efficient (G1) bullet. This isn't to rag on rimfire. Rather, it's to illustrate the important relationship between tunnel length as it pertains to maximum point-blank range and faster-moving bullets in general. Our slower-moving rimfire round falls out of its tunnel at only 125 yards, compared to the M193 round at 327 yards.

Check out this video from Kestrel Ballistics, where Colby Hodnett from Accuracy 1st demonstrates how to determine Max Point Blank using a Kestrel.

WHY MAXIMUM POINT BLANK RANGE MATTERS

Maximum point blank range is crucial for rifle shots where the target only presents itself for a fleeting moment, when there's no time to act and dial or adjust, only time to react and shoot. This is why many hunters rely on it to harvest game. Furthermore, the beauty of establishing MPBR also makes it easy to contend with more basic optics. Using my AR-15 as an example again, suppose I didn't have an easy-to-shoot Leupold Mk5HD with its precise reticle and big-honking exposed turrets. Instead, imagine an Aimpoint Comp M4 mounted to its receiver. The Aimpoint Comp M4's reticle is a small 2-MOA red dot that "freely" floats in the sight picture; there are no other references, and Aimpoints aren't designed to be dialed when shooting. But we know that by adjusting this red dot to coincide with the carbine's MPBR, we can guarantee the shot to land within that 4-inch radius from the point of aim out to 327 yards.

Or maybe it's not an Aimpoint; maybe you're in a field hunting with a rifle equipped with a basic second focal plane duplex-reticle scope with capped turrets–having that scope zeroed for maximum point-blank range would solve a lot of problems.

SHOOTING KNOWLEDGE FROM MDT

ABOUT THE AUTHOR

P.E. Fitch is a nationally published freelance firearms writer and lifelong shooter who covers a wide spectrum of firearms and shooting-related topics ranging from shotguns, rifles, pistols, optics, ammunition, and accessories to firearms training, their history, and their use in sports, both in competition and hunting. In addition to shooting and handloading, he enjoys scratch-cooking and the mixing of craft cocktails. His handle on Instagram and X is @pfitch45 

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