The Ohio Society of Traditional Archers

Outdoor Archer Blog

We want to talk about range finders, a few of the terms and the principles you need to understand for a range finder to be your useful tool out in the Hills, and know that if you want to get the deal of the century.

If you want to learn more about rilfes and and little pulled optics or even just a rangefinder, go to rangefindertoday.com, it’s cool blog for beginners. One most important about how to make sure your rangefinder is aligned properly so it’s giving you the correct reading, you can see that on their website, but today we just want to talk about what these numbers mean and the trigonometry of shooting uphill and downhill.


Leupold Rx-1600i TBR

Leupold Rx-1300i TBR

So I have a little Leupold RX-1600i TBR Laser Rangefinder and Leupold Rx-1300i TBR Laser Rangefinder.

Each of them have a little bit different the 1300 and the 1600 tell you at those distances that’s how far out this should give you a reading if you have a good target. So that the pulse of the laser can go out and be reflected back.

When you’re shooting steep uphill steep downhill angles are just some things you need to know and I want to quickly touch on those. So we have this thing called line of sight or LOS as it’s commonly called.

Line of sight (LOS)

That is the distance between where you are at and where the target is line of sight. If you’re into geometry and trigonometry is the hypotenuse of the right triangle, this longer distance of line of sight will often throw you for a loop.

The reason being is gravity only works on the horizontal distance, so what these angle compensating rangefinders are meant to do to give you your true ballistic range. In other words it does the trigonometry where it measures.

You’re at the angle and the line of sight is out there, we can use trigonometry to quickly and immediately tell you what your true ballistic range is. In other words, what is the horizontal distance upon which gravity will apply against your bullet. That takes a lot of the guesswork out.

Remember in the old days, dad or whoever would say: when you’re shooting uphill or you’re shooting downhill, you need to hold low or you’ll shoot right over the top of it and in your mind you’re like well why is that?

Because it might look like it’s 300 yards out to there but gravity’s only working 200 yards, because it’s such a steep angle, you hold for 200 yards, you set your dial if you have dials like the c.d.s system, you will set your dial for the true ballistic range not the line of sight

So when it comes to range finders, the two key terms are LOS (line of sight) and TBR (true ballistic range) and whether it’s archery, whether it’s a rifle, you want to know your true ballistic range.

So there you have it folks TBR leupold TBR true ballistic range angle compensating ranges finders take care of all that guesswork take care of all the headache for you.