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Night Vision Burris thermals

Does anyone know the if the reticles have defined distances betweeen the has marks?

The FAQs on Burris’ web site said that the reticles are in MILs. When I zero the rifle, I’m going to verify that.

It would really be nice if it was FFP, but doesn’t look like it now.
 
Does anyone know the if the reticles have defined distances betweeen the has marks?

I took the Burris BTS 50 to the range to get it and the rifle zeroed in.

Before I get into that, I discovered that without a riser on the AR-15, the scope is a little low. So, I purchased a YHM riser from Midway:


With part of the riser overhanging the rear of the receiver I was able to mount the scope for the proper height and bring it rearward for a better eye relief. I found that the scope was easier to look through with minimal contortion of the neck in prone, sitting, sitting at the bench and standing. When I was prone, I used the weapon mounted bipod. Unless I was at the bench, I used the Primos Gen 3 Trigger Sticks to rest the rifle on as I would in the field.

I used the toe warmers for a targeted heat source as there was not suitable solar heating available for any metallic tape. I think a smaller heat source would have helped me with getting better precision out of the rifle. Nevertheless, I was able to get nothing worse than ¾ “groups at one hundred yards.

So, I will not complain about the precision of the rifle / thermal combination.

What I did have problems with as an accurate zero. The OEM instructions and videos are reliable except for a couple of things.
1) The windage and elevation adjustments seem a little too coarse. If my groups were a little off on windage or elevation, I would move the cross hairs in the zeroing mode to make the appropriate correction. When I fired the next group, it was off too far in the other direction. Regardless, I am not so proud to admit that there might have been error on my part.
2) I would like to know what value each click on the windage, and elevation adjustments is worth. I could look through the scope and see how far off I was but have no way of knowing if I put in the correct amount of windage and elevation adjustment.

After all my shooting at the paper was done, I removed the toe warmers and stuck them in a soup can at one hundred yards. When I looked through the scope, it looked like the can was glowing. There was also a round four-inch polymer target that emitted some heat as well.

With a few extra rounds, I managed to hit the soup can and the polymer target several times while shooting standing, off the trigger sticks. So, my zero seems adequate for coyotes and that distance and a little beyond.

Now for the part that I really wondered about and that was the holdover value with the different reticles. I was only interested in the reticles with enough dots or indices to get me a good way to holdover for distances outside the 100-yard range that I zeroed the scope in.

BTW, the manual and the scope say to zero the scope in at 25, 50 or 100 meters. 100 yards was the furthest I could sight the rifle in. I figured that was close enough.

If you want to use a visual aid to augment my explanation of each reticle, I suggest that you go to:


Go to pages 10 and 11 to look at the reticle that I will be explaining.

Before I explain the values of the dots / indices, I should explain the methodology used for arriving at the values for those sub-tensions.

Burris says that their reticles are graduated in MILs. A MIL is 3.6 inches at one hundred yards (3600 inches). So, thirty-six inches is 10 MILs at one hundred yards. I stuck a heated toe pad at the top of the target and from the top edge, I measured down thirty-six inches. Then I stuck another toe pad at the bottom of the paper with the bottom edge at 36 inches.

For each reticle, I placed the cross hairs or center dot at the top edge of the top toe pad and looked for where the bottom edge of the bottom toe pad lined up. That would give me a value of 10 MILs in the scope.

Before I go any further, everyone will be glad to know that with an increase in magnification you will be looking through a First Focal Plane thermal scope!!! Now on to further details.

Reticle #2: Every index is worth one MIL. I cannot emphasize this enough; EVERY hash mark is worth one MIL. You will see a half-size hash mark between every larger hash mark. Normally, you would think the smaller hash mark would be worth ½ MIL, but IT IS WORTH ONLY ONE MIL.

I say that because I counted ten hash marks from the top heating pad to the bottom one. I know this is weird and why Burris did that, I will never know but I am only reporting my observations.

So, from the cross hairs to the bottom duplex the total value is 13 MILs. Yes, you read that correctly. Take a look at the diagram on page 10 and you will notice a total of 12 hash marks (6 little hash marks and 6 big hash marks.) That makes 12 MILs plus the bottom duplex gives you 13 MILs.

Reticle #4: From the center dot to the bottom duplex the displacement came up to thirty-six inches as indicated by the bracketed heating pads. So, each dot is worth 2 MILs. That’s TWO MILs! The fourth dot below the center dot is 8 MILs and the bottom duplex makes it 10 MILs.

Reticle #6: There are a total of ten dots below the center dot. Yet only five dots show a displacement of thirty-six inches or 10 MILs. So, each dot is worth 2 MILs. The very bottom dot at the bottom of the scope is 20 MILs. That’s good news if you want to shoot really long distances.

My AR-15 shooting Hornady 55 grain V-max bullets gives me a range of about 720 yards at 10 MILs. I do not think I will be able to identify a target with only a thermal signature at that distance. I am afraid I might have to settle on shooting three hundred yards or less.

Perhaps some folks on this thread that have experience with the Burris thermal can give us some insight on the maximum range capability of this scope.

Reticle #8: I forgot to write down my observations for this reticle. If I recall correctly, each index might be equal to 2 MILs. Don’t take my word for it. Validate this for yourself instead of going by my memory. Edit on 11/25/21: I looked through the scope this morning but wasn't able to set up a 36 inch line at 100 yards. I recall now, why I didn't write anything down about this reticle. The displacement between each hash mark is really large. I think the gaps between the indices are so large that it would be worthless to apply any meaningful holdover. Sorry for any confusion.

Reticle #9: Each index is equal to 2 MILs. From the cross hairs to the bottom duplex the displacement is equal to 10 MILs.

Reticle #10: Every hash mark (small and large) is worth 2 MILs. There are a total of eight hash marks below the center cross hairs for a total displacement of 16 MILs. Adding the displacement of the bottom duplex and you get a total of 18 MILs.

I hope that all that made sense. I could not decide on which reticle was my favorite. I did try the PIP feature with the inset at the top. I need to get use to that feature as I have spent too much time looking through daylight scopes. So, I do not know if I will use it or not.

I do like the fact that this is a FFP thermal scope. So if I want to dial up the magnification on a longer shot and know my holdover, I have a little more confidence in hitting the target. At my elevation and a 40-degree temperature I can expect a 1 MIL holdover for 265 yards and 2 MILs for 355 yards. I cannot see myself shooting past three hundred yards anyway.

I also played around with the stadia-metric range finder. I really like that feature. So please correct me if I am wrong but an average coyote stands 21-24 inches at the shoulder. Just by looking at some photos I would calculate the displacement of the back to the chest to be about ten inches or .25 meters. So, placing the back of the coyote on the top line and the chest on the bottom line should give us a good idea of how far away the doggy is at.

One other thought that I will leave you with is that I might have bought the BTS 35 with the wider angle instead of the BTS 50. The extra magnification is nice but does not help with close and fast-moving animals at night.

Optics planet has another sale on. So I might get the BTS 35 to mount on an AR-15 22LR or an air rifle for small game or night rat hunting.

One other important matter that I must mention is that the range that I shoot at has a cemetery on the other side of the road. We're in a rural area with very little traffic at night. After I turn off all of the range lights before leaving, it does get a little creepy.

I was tempted to look through the scope into the cemetery but was afraid of what I might see! If any of you decide to peek into cemeteries at night let us know the results.

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Optics planet has another sale on. So I might get the BTS 35 to mount on an AR-15 22LR or an air rifle for small game or night rat hunting.
It does seem like the $2300 ish price of the 35 is a reasonable deal. I’m tempted but don’t really need one until next fall…
 
It does seem like the $2300 ish price of the 35 is a reasonable deal. I’m tempted but don’t really need one until next fall…

I succumbed to temptation this morning and ordered the BTS 35 from Optics Planet.

What else would I spend my money on? Whores and whiskey?
 
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I have spent quite a bit of time with the BTS35 out hunting..
I have EASILY positively ID'd deer and hogs out 3-400 yards
I am going to get a 1/2" QD riser as it sits a tad low on an AR flat top and it can be used as a handheld scanner or weapon mounted with a QD mount. It is a very good thermal at a great price point.
 
I had some time this past weekend with the clip-on 35mm Burris Thermal. It was impressive for the price point, and ID-ing Raccoons vs Possum across a field through trees was easy. However, the mounts for the clip ons are still almost vaporware, so be weary buying them just yet.
 
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I had some time this past weekend with the clip-on 35mm Burris Thermal. It was impressive for the price point, and ID-ing Raccoons vs Possum across a field through trees was easy. However, the mounts for the clip ons are still almost vaporware, so be weary buying them just yet.

The lack of mounts for the clip on is what turned me off for now.
 
I mounted the BTS 35 on an air rifle. I like the wider field of view for the shorter distances. I don't envision myself hunting at night without some sort of tripod support or hog saddle but feel more comfortable looking through this scope off-handed than with the BTS 50.

Now if I can only find a place to hunt rats at night!

AirForce TalonSS Burris Thermal.jpg
 
Bumping this back up as I’m trying to decide between the BTS 35 and 50. Hunting a mix of fields and timber thinking the 2.3 on the low end might be more beneficial than the 13.2 on the high end. Also how is the battery life holding up for folks that have had them in the field?
 
Bumping this back up as I’m trying to decide between the BTS 35 and 50. Hunting a mix of fields and timber thinking the 2.3 on the low end might be more beneficial than the 13.2 on the high end. Also how is the battery life holding up for folks that have had them in the field?

I have both. I mounted the BTS 50 on an AR-15 as long shots are more likely for coyote hunting.

I haven't shot any coyotes with it yet. However, I will note that several have come into the calls, I had no trouble locating them with the narrower field of view. They just didn't me much time to line up a shot.

I mounted the BTS 35 on an air rifle as the shooting distance is much shorter. I want to get another BTS 35, when funds are available, to mount on a RRA upper in .22LR later.

The PIP feature sounds like it would be good but I think that I'm the one with the problem using it. I'm an old dog trying to learn new tricks.

There are smarter people than me that like the PIP feature.

The reason that I say that is if you get the BTS 35 you can still use the PIP feature for the longer shots; if you can get use to it.

As far as battery life goes, I use the power saving feature on the scope. I will spend about 8 hours in the field on an evening and go through two batteries.

If you get the 18650 batteries, they have to be the ones with the flat top.

Here's a good article about the 18650 batteries:


The last time I went hunting, the coyotes that I called in hid behind the trees in a draw and the one that did come out only poked his head above a rise for a few seconds.

However, there were mice and rats everywhere. So I got the air rifle out and shot nine of them.

Here's a photo from the Burris BTH 35. It's some pipes laying beside a barn. Notice the white spot in the middle of the photo. That's a mouse or a rat that ran in one of the pipes. The white spot is the heat transfer from his body to the metal pipe.

Mouse Hiding in Steel Pipe (1).jpeg


I've been able to spot rabbits as far away as 400 yards. A few weeks ago, I picked out a cow or a horse at 800-1000 yards away. Field mice and rats were easy to spot as far away as 100 yards but that's a little ambitious for the air rifle.

Here is a video made with the BTH 35 monocular of a field mouse that decided to come out and play after I put the air rifle away. I know that everyone on the hide can keep a secret so please don't tell my friends that drive big pickup trucks, chew tobacco and drink corn liquor that I had as much fun shooting mice as I do hunting coyotes.

 
I have both. I mounted the BTS 50 on an AR-15 as long shots are more likely for coyote hunting.

I haven't shot any coyotes with it yet. However, I will note that several have come into the calls, I had no trouble locating them with the narrower field of view. They just didn't me much time to line up a shot.

I mounted the BTS 35 on an air rifle as the shooting distance is much shorter. I want to get another BTS 35, when funds are available, to mount on a RRA upper in .22LR later.

The PIP feature sounds like it would be good but I think that I'm the one with the problem using it. I'm an old dog trying to learn new tricks.

There are smarter people than me that like the PIP feature.

The reason that I say that is if you get the BTS 35 you can still use the PIP feature for the longer shots; if you can get use to it.

As far as battery life goes, I use the power saving feature on the scope. I will spend about 8 hours in the field on an evening and go through two batteries.

If you get the 18650 batteries, they have to be the ones with the flat top.

Here's a good article about the 18650 batteries:


The last time I went hunting, the coyotes that I called in hid behind the trees in a draw and the one that did come out only poked his head above a rise for a few seconds.

However, there were mice and rats everywhere. So I got the air rifle out and shot nine of them.

Here's a photo from the Burris BTH 35. It's some pipes laying beside a barn. Notice the white spot in the middle of the photo. That's a mouse or a rat that ran in one of the pipes. The white spot is the heat transfer from his body to the metal pipe.

View attachment 7772349

I've been able to spot rabbits as far away as 400 yards. A few weeks ago, I picked out a cow or a horse at 800-1000 yards away. Field mice and rats were easy to spot as far away as 100 yards but that's a little ambitious for the air rifle.

Here is a video made with the BTH 35 monocular of a field mouse that decided to come out and play after I put the air rifle away. I know that everyone on the hide can keep a secret so please don't tell my friends that drive big pickup trucks, chew tobacco and drink corn liquor that I had as much fun shooting mice as I do hunting coyotes.


Any thoughts on how these stack up against the hogster 35?
 
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How far where u when u sighted it in I tried today with hand warmer couldn’t get it zeroed was all over the place gave up

He makes it look easy in this video but the basic principles apply. I used a few more rounds than they do.

One thing that I did to get a more precise aiming point is to fold the hand warmer twice. Basically you’re making a smaller square.

Wrap the square with masking tape then tape it to the cardboard or paper.

Take another hand warmer and fold it into a little square like you did with the other.

Fire a 3-5 shot group. Then go down range and tape the second hand warmer over the group that you just fired.

Now when you get back to your rifle put the cross hairs over the hand warmer that you were aiming at.

When you adjust the cross hairs move them from the aiming point to the group you just fired.

You may have to do this several times but the scope is able to be zeroed.

My apologies if it sounds like I’m insulting your intelligence but those are some things that I learned.

 
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I have one coming that is supposed to land here today. If all goes well, I'll shoot a pig with it this coming weekend.

I also have Leica's Calonox here, so it will be interesting to see them side-by-side.

ILya
Any word on the Calonox? They look like a decent Thermal.
 
What optic are you using with the BTC50? What is the min and max magnification range you would use with this clip-on?
Are you still liking
I've been spending a lot of time with BTH50 and BTC 50 (monocular and clip-on) and I really like them. Given the price, I can not think of anything better for similar money.

ILya
Any update on the BTC 50? What calibers and scopes have you used it with. What distance are you targeting game?
 
I had some time this past weekend with the clip-on 35mm Burris Thermal. It was impressive for the price point, and ID-ing Raccoons vs Possum across a field through trees was easy. However, the mounts for the clip ons are still almost vaporware, so be weary buying them just yet.
Have you had any luck in finding the clip-on mounts?
 
Are you still liking

Any update on the BTC 50? What calibers and scopes have you used it with. What distance are you targeting game?

I do indeed still like it. It has been sitting on a 300 Blackout and it has really worked well.

In terms of image quality, I'd be comfortable taking a shot at a pig out to 250-275 yards depending on the size of the pig. Maybe a bit further, but not much. Essentially, at 300 yards, a 4.5ft object subtends ~15 pixels. For reasonably decent aiming, you need about 12-15 pixels (Johnson criteria), but in practical terms when hunting I want to stay on a safe side of that by a little bit.

It has not skipped a beat so far and I am heading out with it (and several other thermals) for another pig hunt next month.

Between 50mm lens and a few more pixels that most QVGA thermals, it is probably my choice out of the ~$3k clip-ons I have seen to date.

ILya
 
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I've been spending a lot of time with BTH50 and BTC 50 (monocular and clip-on) and I really like them. Given the price, I can not think of anything better for similar money.

ILya
ILya,

Have you spent time behind the Leica Calonox View? I have the BTS35, which was a bit of a compromise for me as I wanted lower mag and a larger field of view to be used as either a handheld or as a scope, so I chose it over the BTS50. But the Leica Calonox view has intrigued me and I’m thinking it would make a really good handheld which may lead me to upgrading the scope to the BTS50. Curious what you think of the Calonox view if you’ve spent any time behind it.
 
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Update: I’ve decided to go iRay Zoom ZH38 over the Leica.
 
Has anyone used the Burris in hot humid conditions yet? Still effective?

It wasn't hot that day but there was 100% humidity in the air and it worked great. I think the temperature was about the mid 40s.
 
That’s the other bit…hot and humid. Thanks Longshot. Update if you use it when it warms up please sir
 
Anyone here that’s used both the BTC50 and the Hogster C? I’d love to hear a direct comparison between those two units.
 
Who has the best street prices on the Burris Thermals?

I got mine from Optics Planet. Use the discount code 704TAC to get 5% off. Signup for their email and text alerts for flash sales and savings.

Yes, I know that you can get inundated with lots of emails and texts from them but for me, it hasn't been that bad. I got 11% for a veterans day sale last November.
 
Just wondering what's the current word on the street for these BTS35. Are most people happy with theirs ? Any issue with zero drift ?
 
Just wondering what's the current word on the street for these BTS35. Are most people happy with theirs ? Any issue with zero drift ?

I have one and really like it. It's on my air rifle. The BTS50 is on an Ar-15 and works great as well.
 
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I purchased two more BTS35 thermals on sale at Midway. Put one on an AirForce Condor in .25 caliber and another on an AR-15 22LR.

They’ve been good for me.
 
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Any other options for a good cantilever QD mount? From what I can tell, these have the same mount as the Steiner S35 and probably the C35.
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