Rangefinders

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Rangefinders

Without question, rangefinders play one of the most important roles when it comes to hunting where bullet placement is the key factor in ensuring swift, ethical kills.

Invest in a Quality Rangefinder So When the Opportunity Presents Itself You Can Confidently Make an Accurate Shot

By Eric Martin

You spend years building application points, months prepping, planning and getting in shape, hours at the range making sure your rifle and scope are dialed and ready. The season opens, and when an opportunity finally presents itself, the first piece of gear you’ll depend on, your rangefinder, is one that is often overlooked in all the hype over the latest and greatest pieces of hunting equipment. 

This exact scenario played out for me last fall. Having drawn an elk tag that I had literally spent one third of my life applying for, I sat atop a small, windswept ridge as the sun crept over the horizon, staring across the canyon at the largest bull I had ever had in my crosshairs. The first things to go through my head weren’t if my camo pattern matched my surroundings, or if my boots had enough insulation. The only thing I cared about was knowing how far away he was. 

It wasn’t all that long ago such situations required a good amount of experience in the field, and an even greater amount of sheer luck. On those early hunting trips with my father, animals always seemed to appear in distance factors of fifty yards. “He’s about 250” or “that ridge has to be 400”, my dad would proclaim. Sometimes our highly unscientific calculations resulted in a filled tag. Often, it ended with a fleeting glimpse of the backside of an unscathed animal, and an education in bullet trajectory. Thankfully, times have changed, and technology, which can deliver confidence and accuracy, can be carried in a shirt pocket every time you hit the field. 

As I watched the bull feed out of the trees into the open hillside, I didn’t have to estimate the distance or guess what adjustment to make. A quick check with my rangefinder told me everything I needed to know. He took two more steps; I checked again to confirm the reading, quickly referenced the ballistic information for my rifle, and fired a single shot. The bull never took another step. 

Without question, rangefinders play one of the most important roles in consistently placing shots on target, and when it comes to hunting, bullet placement is the key factor in ensuring swift, ethical kills. Knowing the exact distance to targets allows for precise adjustments and compensation, or perhaps ruling out a shot all together. I can say with one hundred percent certainty, regardless of how large the bull was, had I not known the distance in that situation, I would have never even attempted a shot. The risk of potentially wounding an animal due to a misjudged shot is simply too great a risk to take. 

WHAT TO LOOK FOR

While few will argue the importance of a quality rangefinder, the myriad of styles, features and options available can leave many feeling overwhelmed and confused. Let’s get started with a quick breakdown of what to look for, and maybe also dispel a few common misconceptions.  

Typical rangefinders work by emitting a class 1 (invisible) laser which reflects off the desired target and the returning signal is read by high speed sensors inside the unit. Using the known speed of light, processors in the unit can then calculate the time it took to receive the return signal, and then convert to distance traveled. The process seems relatively simple, yet it is anything but. 

PROCESSOR: Just like computers or phones, some units employ processors that are faster and more powerful than others. When it comes to rangefinders, this means some units can compute more readings, faster readings, and calculate faster data than other units. Early generation rangefinders often based readings off a single return signal, which often resulted in erroneous readings, whereas newer units commonly emit pulses of signals that return more data back to the unit allowing for tighter averaging calculations and a much more accurate readout. 

The key to getting an accurate readout is doing your best to control what data is being sent back to the machine. Looking at units in a store you can quickly see a variety of aperture sizes. Generally, larger apertures can better collect larger amounts of reflected signals, in turn produce faster and more accurate readings.

SIZE OF LASER BEAM: Have you ever noticed how a flashlight beam on your living room wall may be a small spot, but it can illuminate your neighbor’s house across the street? The beam coming out of a rangefinder acts much the same way. The divergence, or spread, of the beam can vary greatly from one unit to another. Some units will state what this may be, while it can be hard if not impossible to find on others. Basically, as the beam spreads over distance, it may be picking up readings from objects that are not the target. When these readings return along with the target readings, the unit may average all the readings and give a false distance. Sometimes, if the target is small enough, and there is a lot of surrounding interference, you may not get a target reading at all. Too tight of a beam can also cause problems, as at longer distances, it may be difficult to hold the unit steady enough to get a solid reading on the target. 

Generally, higher quality units have sensors and processors that can filter such readings and eliminate data which doesn’t fall in line with the majority of the returning signal. Another trick is to adjust your target for the clearest or largest alternate target. A deer at the base of a rim rock may be shielded by brush or trees in the foreground, but by focusing your rangefinder on the rock face just above and behind the deer, you may get a cleaner signal and quicker reading as to the general distance to the deer. 

DISTANCE CAPABILITY: Speaking of distance, the first thing many people notice about rangefinders is they seem to be classed by the distance they’re capable of reading, which results in many people buying a unit ‘rated’ for distances they may not choose to shoot farther than. This isn’t really accurate. A 600-yard unit may only read to that distance under perfect weather conditions, and only with a large, highly reflective target. You may get peak readings on a white barn on a clear day, but I guarantee you won’t get the same reading on a black bear in the rain at dusk. Because the units calculate based off the speed of light (in a vacuum), environmental factors such as dust, smoke, heat waves and humidity can slow and disrupt the laser beam, hindering performance. 

Last year I watched two bucks fighting in a coastal clear cut in thick fog for over five minutes before the fog blew out and I could get a reading on the deer. In real world hunting scenarios, plan on a unit producing accurate readings at about 60 to 70 percent of the rated distance. If you plan on shooting 600 yards, don’t buy a 600-yard unit; buy a rangefinder capable of 1,000 yards so you will be sure to get good readings out to your effective range. 

ANGLE ADJUSTMENT: Another key feature to look for is a rangefinder that calculates and adjusts for angles. If a deer is 400 yards away on flat ground, you shoot for that range. But what if that same deer is 400 yards in front of you, and you are 600 feet up a canyon wall looking down at him? How far do you shoot now? The Pythagorean Theorem says the distance to the deer is 447 yards. Gravity, however, never took a math class. Gravity only acts on an object over the horizontal distance it travels. A non-angle compensating rangefinder would read the actual distance at 447, and you would miss high; the horizontal distance over ground from you to the deer, as read by an angle compensating rangefinder, would be 400 yards. Because gravity only acts on your bullet or arrow for the horizontal distance it travels, it is imperative you shoot for this distance, and not the actual line of site distance. If you plan on hunting areas where steep angle shots are a possibility, be sure to select a model with angle compensation.

CUSTOMIZE OPTIONS: Another thing to look for is models that have various modes or settings which allow customizing the performance based on the conditions being encountered. Such modes may allow scanning; allowing the user to pan over a target, or following a moving target, to get up to the moment progress on distance. Other settings may tell the unit to calculate the return signal differently due to rain, brush or irregular target shapes or backgrounds. Some of the most advanced models can even be uploaded with your hunt conditions such as elevation and temperature, and even your specific ballistic data, to produce some of the most accurate readings available.  

MAGNIFICATION: Another notable feature on rangefinders is that most include some degree of magnification. Is this so they can double as a monocular in a pinch for quick glassing? Well, to some degree you can do this, but the magnification is actually to help improve your view on prospective targets; enlarging the target and allowing a bigger reference points on where to aim the rangefinder. Most units will be in the 4x, 6x, or 8x magnification range, and unless you really plan on a lot of long range target acquisition, the lower magnifications seem to allow a bit faster target reference in the viewfinder, as well as performing better in low light situations. Models with larger objective lenses also benefit low light usage. 

LCD READOUTS: In low light, another troublesome area for some rangefinders is being able to read the display. Many displays feature LCD readouts with black numbers, which can be incredibly hard to see on dark backgrounds or in low light. When I tried to get readings on my bull, I had to keep panning the rangefinder up to the sky so I could read the black display, because the numbers blended in with the dark, pre-dawn hillside. Some units have backlit displays, or illuminated numbering which makes viewing in all lighting situations a breeze, but may also be hard to read in bright sunlight. 

EASE OF USE: Lastly, look at overall construction and design layout. I personally think it’s important that a rangefinder has some sort of designation as being waterproof or water resistant. Are the activation and mode adjustment buttons well sized and easily located? Can they be manipulated with gloves? Are they in a place where they can be accidentally bumped or adjusted when the unit is jostling around in your pocket? What about the battery? Does the unit specify battery life? Can the battery be easily changed, and is it a common size? I once had a rangefinder that had such an irregular battery no store in the small town I lived even carried them. I like units that use common batteries, not rechargeable, so that in a pinch, you may be able to rob batteries out of a flashlight or radio in camp and not be stuck up a creek with a dead rangefinder. 

When you factor in all the time and expense that goes in to each hunting trip, not to mention the concern for the animals that you pursue, it only makes sense to invest in a quality rangefinder so that when the opportunity of a lifetime presents itself you can confidently make an accurate shot.  

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