Ranging coyotes with the Thermion X51FI-300 reticle.

JTPinTX

Custom Call Maker
Y'all may have to bear with me a bit on this post. I'm trying to figure out how to get some images posted so it may be a train wreck until I get it figured out. I think that for some of the Thermion users this may be of interest though.

Starting off I hunt in open country and really wanted a thermal with LRF. That didn't happen because it wouldn't hold zero, so I ended up with a Thermion. It holds zero great, but all of you guys know how hard it is learning to judge distance through a thermal. I do LR shooting and know how to range with a reticle so I started my search to try find something that would work.

First off, on the Thermion there are 3 "scalable" reticles that are for all practical purposes the same as a FFP reticle. Meaning that the size scales up and down with changes in power, making them stay the same size in relation to the target image at all magnifications, which is critical. Two of those reticles are MIL based reticles, so if you are used to doing that, just use one of them.

The other one though is similar in looks to a BDC reticle, but has sub-tensions based on ranging. That reticle is the X51FI-300. Of course with Pulsar being a European country those sub-tensions are based on the game over there, which is fox, roe deer, and boar. The Pulsar website gives all the data on the measurements they use and how to use it here, page 13:

https://issuu.com/yukon2/docs/thermion_reticle_catalogue?fr=sZmMzMjI5ODQ5

Converting cm to inches I found that for all practical purposes the number they use for roe deer is very close to what a guy needs for the body depth on coyotes. I have always used 8"-9" for the body depth on a coyote in my part of the world. Ours are mostly smaller western coyotes. I know that will vary parts of the country and young vs mature animals. Any time you are ranging with a reticle there is give and take, and numbers are not absolute. It should give you a pretty good idea though.

I have been using this reticle and ranging with it like this for a couple months now. It appears to me that the numbers are pretty close. Here is a hand drawn version of the reticle from my notes, and the calculations I made, along with distances. The only thing that was not a direct calculation, but instead a derived number is the "C" distance for the coyote. At the end I will also post up a video of a coyote I shot at a laser ranged 135 yards and y'all can look at that and compare to the "C" distance of 132 yards.

If you guys look all this over and think there are problems/issues with my math or any of my premises, by all means let me know. I would love for some of you guys to try and and either verify or debunk me. I want things that work and if there are problems I would like to know. I would also like to know if it helps anyone as well.

Video:





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This thread never got any traction the first time around, not sure why. Seems like there would at least be a few folks interested in it, but maybe it was wrong time of year. I had planned to update with some real world tests but then didn't due to the lack of interest. Earlier this week though SEMOmike had a thread asking about ranging with a Super Hogster reticle so I decided I would go ahead and do my tests, post up the images, and see if it would help anyone. SEMOmike, maybe you can use some of it to help you along in your quest for reticle ranging.

I have a coyote target I made. It is made of 3/8" copolymer polypro plastic. Very durable. It has a 4" steel vital area. I practice with it and taught my daughter to shoot coyotes on it. As far as I can tell it is very close to true coyote size for our area. I named her Jezebel, lol. Here is a picture of Jezebel, she is 18" tall at the shoulder and has a depth of body cavity at the shoulder that is 8.5". I have compared her to real life dead coyotes from my area several times and found her to be pretty dang accurate. Maybe a hair small for a big male, but not by too much.

Without rehashing all the calculations above, the breakdowns are this to bracket body cavity depth:

Bottom line = 135 yards.
Middle line = 200 yards.
Top line = 300 yards.

With good snow cover on the ground I set Jezebel out, used my Leica 1600 to shoot accurate distances, and took these stills with the Thermion. It might not be absolutely exact but they turned out pretty dang close. Close enough that different size or aspect angle coyotes could shift it either way. Basically for me it puts coyotes in 3 categories. Bottom line should be dead coyote. Middle line is 200 where I am zeroed, so anything inside that should be point and shoot with no holdover. Top line is 300 and do-able, but I need to be thinking about correct holdover.

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Nice work. I have a thermion but never used that reticle. I’m going to try it out now since you’ve demonstrated that it can be a pretty quick way to roughly determine range. I think it could be very useful. Thanks for the information.
 
Top photo 135 yards
Middle photo 200 yards
Bottom photo 300 yards.

Bottom photo is not near as good because I was looking through a wire mesh fence and also just had the rifle balanced on the door of the truck while trying to simultaneously press the photo button. I was pretty shaky taking that photo.

It is not perfect rangefinding. But it can let you know pretty quick if they are in what I call point blank range, anything under 200.
 
Thanks JTP...I use a reticle very similar to this one in my Thermion...I will look at this reticle and see how close they are. This will help some to get a rough estimate at least.

Gene
 
Three of the Thermion reticles as scalable and will stay true at any magnification. The X51Fi-300, the M56 Fi, and the M57Fi. All the other reticles are not scalable and the increments will vary with magnification. For the non-scalable reticles they will only be accurate at one magnification.
 
Like my friend, you have the Pulsar Thermion XP50 and you are all very happy with this excellent, ergonomic and beautiful device. It just lacks the laser rangefinder to be perfect. So you have to make up for this by using the reticle to estimate the distances to the targets. I was asking myself and you too, if the Pulsar Trail 2 lrf XP50 or XQ50 with the magnesium alloy body (which should theoretically guarantee the conservation of the POI) and the built-in laser night rangefinder, could represent a valid alternative choice.
 
Ernest, mine is a XQ50 Thermion, not XP50.

Originally I bought an XQ50 LRF Trail. That was my first choice. But it had issues and would not hold zero for me. The Trail 2 was not out yet at that point so I went with the Thermion for the reliable POI.

The Trail 2 LRF would be very viable but my budget will not allow me to trade at this point.
 
The Thermion XQ50 is also a great device. I am waiting for the Super Hogster to arrive in Italy, but who knows when it will arrive ... Could the alternative be the Pulsar Trail 2 XQ50 lrf?
 
I have a friend with a Trail 2 XQ50 LRF. He likes it a lot. But I have a couple other friends with Super Hogsters and they like them too. Budget, needs, and availability all play together. Several different ways to get there.
 
JPT, I just checked on my Thermion XP50 and I am using the X51Fi-300 reticle...I have a coyote silhouette and I am going to set it at the ranges you have listed and see what I come up with.

Thanks

Gene
 
I would love to see some others input. Feel free to post the pictures up on this thread if you get some. To swap from video mode to still shot mode in the Thermion, just hold the record button down for a few seconds and you will see the icon swap from video to still. At that point a press of the button takes a still shot. To swap back to video same thing. Just hold it down until the icon changes.

I have an old coyote decoy, maybe it is a Flambeau? Not sure. Anyways I may set it out and see what it looks like as well. Just as a comparison.
 
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