Leupold Rangefinder: Archery Mode?

[jonesn3]

I have a Leupold RX-1600i TBR/W rangefinder that I use for everything. Honestly, it probably does way more than I actually use it for...which is basically just LOS and Angle (for rifle ballistics app input) or Horizontal distance for archery. That said, the "Bow Mode" seems strange from reading the user manual and the included example: 40yds*cos(40deg)=30.6 yds=horizontal distance. The manual says 34 yds. Whats going on here? Is Leupold doing some fancy internal calculation to come up with "equivalent horizontal distance" as its referred to in the user manual? Considering the rangefinder doesn't take arrow weight or speed inputs, it seems odd they would attempt to estimate the "shoot for" distance. The cut charts for my particular arrow weight and velocity don't jive with this example either. Then again I haven't exactly been practicing much on 40 deg downhill shots to confirm.

The dimensions in the example Leupold provides seem like a pretty unlikely hunting scenario for a treestand (like the illustration shows), but seems like something a western hunter might want to understand before taking a shot based on a calculated "equivalent" distance.

Does anybody have insights? Thanks.

From user manual:





Other similar and newer rangefinders from Leupold (e.g. RX-1400i TBR/W) appear to have the same feature and stated example in the user manual.

 

[Blockcaver]

I’ve got the same Leupold rangefinder as you. Have only used it in archery mode. Works very well for me on decline shots both in my mountainous back yard and hunting mountain game…sheep and caribou come to mind.

The illustrated example in the manual appears to possibly be in error? My Leupold matched up with my horribly slow old Leica that takes over 2 seconds to spit out the angle corrected yardage.

Might have to take both rangefinders out behind the house along with the calculator program today.

 

[jonesn3]

Thanks for the feedback. It’s a good rangefinder for me. This part of the user manual has always bothered me but just went with it. After I posted this, I saw some past forum posts either on AT or elsewhere for previous models but the manual has the same “example”. It might be a typo, the discussion I read was 40 yd LOS with 30 deg decline which was 34.6 yds horizontal, very close but still not the same as the stated example. I’m sure it’s not a big deal, just wanting to fully understand the my equipment

 

[PaBone]

I have the same rangefinder and only use it in bow mode, since that's the only weapon I use anymore. Mine started losing some of the internal graphics last year and I should of sent it back last year but forgot. This year it's not working at all and just sent it back to Leupold last week. Hoping I get it back before archery season.

 

[jonesn3]

I have the same rangefinder and only use it in bow mode, since that's the only weapon I use anymore. Mine started losing some of the internal graphics last year and I should of sent it back last year but forgot. This year it's not working at all and just sent it back to Leupold last week. Hoping I get it back before archery season.

I'd be curious to know how your CS experience goes, and if they replace with the same or new model.

 

[Beendare]

My older Leopold calcs the horizontal distance and has been dead on

 

[Blockcaver]

So I just finished a test comparing my old 2013 model year "slow" Leica 1000R vs my Leupold RX1600i-TBR w/DNA from 2018:

I took took multiple ranges from positions directly above my archery target at 30 yds, 50 yds, 70 yds, 90 yds, then a side-hill steep down hill range(s) at 80 yds. Each position was ranging downhill at -21* to -23*.

I also ranged a position uphill at +6* .

Corrected yardage correlated "exactly" on 3 of the 6 positions and varied by .5 to 1 yard on the other 3. The Leica angle corrected yardage totaled 406 yards, and it only reads out to the nearest yard. The Leupold corrected yardage totaled 408.5 yards, but it also reads to the nearest 0.1 yards.

Solving the Lecia Line of sight yardage and angle corrected yardage for the calculated angle resulted in a 3 of the Leica angles being 1* to 2* steeper than the Leupold indicated. The other 3 angles were identical.

My conclusion is the Leica and Leupold I have both calculate Horizontal distance by using the cos of the angle the rangefinder is held at X (times) the line of sight distance the rangefinder reports.

And back to the original poster's question....I believe he uncovered an error in the illustrated example in the Leupold manual.

 

[jonesn3]

Thanks for testing and reporting back! Glad it just appears to be a typo in the user manual

 

[jonesn3]

So I just finished a test comparing my old 2013 model year "slow" Leica 1000R vs my Leupold RX1600i-TBR w/DNA from 2018:

I took took multiple ranges from positions directly above my archery target at 30 yds, 50 yds, 70 yds, 90 yds, then a side-hill steep down hill range(s) at 80 yds. Each position was ranging downhill at -21* to -23*.

I also ranged a position uphill at +6* .

Corrected yardage correlated "exactly" on 3 of the 6 positions and varied by .5 to 1 yard on the other 3. The Leica angle corrected yardage totaled 406 yards, and it only reads out to the nearest yard. The Leupold corrected yardage totaled 408.5 yards, but it also reads to the nearest 0.1 yards.

Solving the Lecia Line of sight yardage and angle corrected yardage for the calculated angle resulted in a 3 of the Leica angles being 1* to 2* steeper than the Leupold indicated. The other 3 angles were identical.

My conclusion is the Leica and Leupold I have both calculate Horizontal distance by using the cos of the angle the rangefinder is held at X (times) the line of sight distance the rangefinder reports.

And back to the original poster's question....I believe he uncovered an error in the illustrated example in the Leupold manual.

This question came up again yesterday for me while discussing with buddies at the archery range. I called Leupold CS just now, and they did say that the RX1600i-TBR w/ DNA is using some internal ballistic calculation to display a "ballistically equivalent horizontal distance" that is more than just the horizontal distance based on trig (Hz=LOS*cos(angle)) for the BOW Mode. I assume there must be an average ballistic coefficient and speed assumed since there is no way to input bow/arrow setup.

Now I feel like I need to do some DIY shooting/testing

 

[jonesn3]

I ended up testing the the Leupold RX-1600i TBR/W at a couple distances and angles. Used the BOW mode and the Trig mode (gives the horizontal, cos(angle), and vertical components). Both methods on the same rangefinder gave the same results. The main difference I saw between those two methods is the Trig mode displayed LOS, Horizontal, Vertical, and angle whereas Bow mode only gives Horizontal distance (to 1 decimal) and the angle. I confirmed the results with a Vortex Ranger 1600 rangefinder and got the same results.

Distance 1: hz 68.5-69 yds, -16 deg slope

Distance 2: hz 38.7-39 yds, +29 deg slope

Despite what the user manual and CS says, for the Leupold rangefinder with “BOW” mode and not having any bow/arrow inputs entered into the rangefinder, I feel pretty confident it’s simply giving a horizontal distance. The example in the manual has an error in my opinion.

 

[BigSky]

Just so there's no confusion for novices who may be reading this, there's no need for any bow or arrow inputs unless you are using the version that can tell you if you are going to clear an obstacle such as a tree branch. Otherwise, the straight line distance is the exact same for an arrow, of any weight and configuration, flying at 330 feet per second as it is for an arrow of any weight or configuration, flying at 250 feet per second. The distance doesn't change. That's what the range finder is telling you, the distance (horizontal distance). It has absolutely nothing to do with the "ballistics" of your particular setup.

Now, I know there are rangefinders and ballistic programs that can do that. I even have a couple. However, the straight line distance doesn't change depending on one's components and speed. Your sight is set at specific yardages and that is what you are trying to determine, the straight line (horizontal) distance to your target that is at an upward or downward angle and has a line of sight distance that would cause you to use the incorrect sight pin.