Maximum Point Blank Range Sighting-In —Holding on Fur

Take the guesswork out of bullet drop by sighting-in for maximizing a rifle’s lethal range.

Maximum Point Blank Range Sighting-In —Holding on Fur

This illustrates the benefit of MPBR sighting-in if the rifle and shooter do their parts — four shots in a coyote’s 6-inch kill zone, holding dead-on from 100 to 320 yards.

Scott Huber turned and shot me a disgusted look. While he had just made an incredible shot — rugging out a trotting coyote at 250 yards — its mate had escaped a volley of follow-up shots. Scott, an animal damage control agent for South Dakota, knew full well that an educated coyote can be tough to fool a second time, and it was his job to rid the ranch we were hunting on of these livestock depredating canines.

Something had been bugging me all morning, and as we picked up our gear and headed off to the next setup, I finally popped the question: “Why do you hunt with a fixed-power scope?” Scott’s rifle, chambered in .22-250 Rem., carried a Plain Jane 6X riflescope that reminded me of bygone days at my family’s northern Minnesota deer camp. It seemed to me that someone who hunts coyotes for a living would take advantage of the newest technology — such as the 4-12X variable-powered riflescope with a bullet drop compensating (BDC) reticle that sat on top of my favorite fur gun. 

While this occurred on a hunt years ago, his answer was so simple that it made perfect sense and has stuck with me ever since — that he subscribes to the K.I.S.S. (keep it simple, stupid) graduate school of fur hunting.  He explained that the 6-power magnification his riflescope provided was perfect for the wide range of shooting he does — good for both close and long range — and that (here’s the kicker) he hunts so much with this rifle/scope setup that he can quickly and accurately judge the distance to a coyote by how large it appears in the scope. He also had his scope set up to take full advantage of the .22-250 Rem.’s long-range capabilities, by sighting-in so he could hold on center mass from zero out to beyond 300 yards. (More on that in a minute.) 

Seasoned predator hunters know that things can and often do happen quickly when critters show up unannounced — that they might encounter fur targets at any conceivable range, and at every possible angle, from in their lap out to the horizon, and have to make quick shot decisions in the blink of an eye. That’s why a fixed-power scope makes sense, and why when using a variable-power scope, it’s a good idea to keep it set at its lowest magnification when calling, figuring that if a critter shows up at close range it will allow the hunter the widest field-of-view for quick target acquisition. If a critter hangs up at long range, there will be plenty of time to crank up the power to full magnification.  

BDC riflescopes with multiple-line reticles or dial-up turrets are all the rage these days — their manufacturers claiming they take all of the guesswork out of long-range shooting. These scopes utilize hash marks or adjustable turrets to remove the necessity of hold-over. The shooter sights-in at 100 yards and then either selects the hash mark that corresponds with a predetermined distance or dials the turret to pre-programmed yardages. Some optics companies even custom program scopes. All the owner has to do is provide some basic ballistic information. Those hunters who utilize these tools often have a yardage card taped to the stock of their rifle that they can “quickly” reference to select the proper hash mark or dial in the shot. Yes, BDC riflescopes perform as advertised — IF AND WHEN there is adequate time to quickly and accurately calculate range and select the proper setting while staying on target. See the problem?

 

Reaching Out There with Confidence

But the truth of the matter is that many predator hunters rely on standard reticles, sighting-in at 100 or 200 yards and compensating for long-range shots by holding high on, or even over, animals at extreme ranges. Say they’re shooting a 50-grain bullet in a rifle chambered for the aforementioned .22-250 Rem. that exits the barrel at 3,800-plus fps. Sighted-in at 100 yards — depending on the specific bullet weight and design — it will drop about 2 inches at 200 yards, 8 inches at 300 yards and 30 inches at 400 yards. Keep in mind that the kill zone of a coyote is approximately 6 inches. So at 225 yards and beyond hold-over is required. The same bullet zeroed at 200 yards will hit about an inch high at 100 yards and drop about 5.5 inches at 300 yards and 17 inches at 400 yards. And while this method might be less cumbersome than using a BDC reticle, making a lethal shot at long distance requires a fairly accurate guesstimation of range and a good idea of where to hold. Add a moving target and, well, things can get complicated.

Ballistic programs such as Nikon Optic’s Spot On calculator take the guesswork out of computing a bullet’s maximum point blank range.
Ballistic programs such as Nikon Optic’s Spot On calculator take the guesswork out of computing a bullet’s maximum point blank range.

Calculating MPBR

Thankfully, there’s a better way — a sighting-in method referred to as Maximum Point Blank Range (MPBR), which refers to the distance out to which the shooter can hold the crosshairs on center mass and achieve a lethal hit within an animal’s vitals. In the case of medium-sized critters such as coyotes, bobcats and foxes we’re talking a 6-inch diameter circle — that’s 3 inches above and 3 inches below point of aim. Imagine shooting at a 6-inch-diameter paper plate with an X marking its center. The bullet will not rise above or fall below the top or bottom of the pie plate from zero yards out to the bullet’s determined MPBR. Another way to visualize this is to imagine shooting through a 6-inch pipe (say one that’s 400 yards long!). The line of sight is exactly down the center of the pipe and the scope is adjusted so that the bullet’s path will never rise higher than the top of the pipe or fall below the bottom edge of the pipe until it reaches its maximum point blank range. 

So, how does a shooter determine MPBR for his or her favorite fur rifle? Fortunately, there’s no shortage of online calculators designed to calculate MPBR for any of the popular (and some not so popular) cartridge/bullet combos used to collect fur. A quick Google search is all that’s needed to locate an easy-to-use ballistic calculator. There are also a bunch of ballistic calculator apps for smartphones and tablets that quickly calculate MPBR. These are useful because shooters can take them to range and dial up a rifle’s MPBR and then verify it on paper.  For the purpose of this discussion, I used Nikon Optic’s Spot-On online calculator to determine the MPBR for three popular fur calibers, as an example. Ranges were calculated for the 6-inch kill zone of a coyote. 

.223 Rem./53-grain Hornady HP/3,300 fps muzzle velocity/0.223 B.C.

Zero = 245 yards

Maximum PBR = 286 yards

100-yard sight-in = 2.34 inches high

 

.22-250 Rem./50-grain JHP/3,850 fps muzzle velocity/0.207 B.C.

Zero = 275 yards

Maximum PBR = 319 yards

100-yard sight-in = 2.11 inches high

 

.243 Win. /55-grain Varmageddon/3,800 fps muzzle velocity/0.192 B.C.

Zero = 265 yards

Maximum PBR = 308 yards

100-yard sight-in = 2.11 inches high

  These examples show that by sighting-in a rifle using the MPBR method, achieving on-target shots out to 300 yards and beyond without adjusting the hold for bullet drop is possible — and that a bullet’s velocity and B.C. affect its MPBR. The greater the speed and/or the higher the B.C, the greater the MPBR. 

Hunters in the open terrain of the West recognize the need for a rifle/cartridge/bullet combos that are capable of long range shots.
Hunters in the open terrain of the West recognize the need for a rifle/cartridge/bullet combos that are capable of long range shots.

An important caveat: Rifle accuracy and shooter error are not entered into these calculations — real-world variables that should be considered. Ballistics programs don’t take grouping into account — they assume a single point of impact for a given zero at a given distance. For example, let’s say a rifle is shooting MOA — roughly 1 inch at 100 yards, and plenty accurate for anchoring a coyote at that range. But extend that range to the outer perimeters of the bullet’s calculated MBPR (175 and 320 yards in the .22-250 Rem. example) and it’s easy to see that with the MOA extended to about 1.75 and 3 inches, respectively, the bullet could conceivably fall outside of the 6-inch kill zone of a coyote. The shooter can either roll the dice on longer shots or decrease the size of the vital zone for MPBR calculations to account for these factors. 

Hunters who have the luxury of a rifle range where they can shoot out to several hundred yards, can check the results of the website/app calculations. Or, those who enjoy punching paper can determine MPBR through trial and error. Using a 6-inch diameter target, zero the rifle 1 inch high at 100 yards (.22-250 Rem. 50-grain bullet, as an example), then move back from the target to various distances (200, 300, 400 yards, etc.) and measure the range of the highest hit and the extreme distance when the bullet falls below this chosen “vital zone” (3 inches below point of aim). In this example, the zero will be approximately 200 yards, and by 300 yards the bullet will have dropped about 2.5 inches below the 6-inch vital zone. This means the shooter will need to adjust hold at 265 yards and beyond. It also means he or she is not taking full advantage of the bullet’s MPBR capabilities. 

Now adjust the zero so that the bullet hits 2 inches high at 100 yards. Peak trajectory (highest striking point within the vital area) should fall between 150 and 175 yards (where the bullet drifts to the extreme top of the 6-inch circle — 3 inches above point of aim), and at about 320 yards before it drops out of the 6-inch kill zone (3 inches below point of aim). In this case, MPBR has been confirmed and the shooter can hold dead-on target without the bullet traveling more than 3 inches above or below point of aim. Those shooters who don’t have a 400-yard range will have to trust the math provided by their ballistic calculator and sight-in accordingly.  

By keeping things simple and applying the MPBR method of sighting-in a rifle, fur hunters can possess the confidence to make lethal shots out to 300 yards and beyond without the worry of knowing the precise distance to the animal. Forget about hold-over, dealing with the clutter of hash marks or fumbling with ranging turrets, and focus on making the shot.



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