IR thermometer

nuclear_shooter

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Minuteman
Jun 28, 2013
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I'm looking for an IR thermometer to measure bullet/chamber/barrel temps (mainly for bullet temps, but the rest might be interesting to look at). My question is, are the cheaper ones ($15-$30 range) worth getting? Here is one example: HDE® Temperature Gun Infrared Thermometer w/ Laser Sight - Amazon.com. It gets a bunch of good reviews but also a fair number of bad reviews. The other option is to get the Fluke offering, which is almost 5x the price of the cheaper ones Fluke 62 MAX Infrared Thermometer, -22 to 932 Degrees F Range: Amazon.com: Industrial & Scientific. I am generally of the mindset to buy once cry once, but I also don't want to spend money if I don't have to ($100 seems like a bit much to measure ammo temps). So, does anybody have any experience with the cheaper IR thermometers? I have gone with the cheaper version in the past (calipers, slings, et cetera) and almost always end up regretting it.... but sometimes it does work out.
 
You been watching TRex on youtube, I was going to grab one as well, but if you let your Ammo get to the same temp as your Rifle you wont have to worry about that and then you got money for 3 more boxes of Ammo,

other than that store the next round in ya Butt crack and adjust for 98.6*f. lololololol

Sorry its just that I've been hangin out with VJJPunisher too much

blessin's John
 
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Yeah, or better yet I could just put the money toward a Kestrel let my ammo come into equilibrium with the air temp...

I mainly shoot H1000 which is probably better than some other powder but I couldn't find anybodies actual data online and got curious :D.
 
Yeah, or better yet I could just put the money toward a Kestrel let my ammo come into equilibrium with the air temp...

I mainly shoot H1000 which is probably better than some other powder but I couldn't find anybodies actual data online and got curious :D.

Wel I would get the Kestrel First because there are 3 or 4 things on that That you really need to know over anything else,

John
 
If you're going to go that route.. go cheap. IR thermometers are great for obtaining a "general" temperature or temperature difference (delta-T) but not great at obtaining exact temperatures. It's not that they're incapable of exact temps...it's just that there's no way to compensate for emissivity and they're easily fooled by reflected energy when shooting reflective surfaces. Gun parts, bullets, etc. are very reflective (in an IR sense)
 
If you're going to go that route.. go cheap. IR thermometers are great for obtaining a "general" temperature or temperature difference (delta-T) but not great at obtaining exact temperatures. It's not that they're incapable of exact temps...it's just that there's no way to compensate for emissivity and they're easily fooled by reflected energy when shooting reflective surfaces. Gun parts, bullets, etc. are very reflective (in an IR sense)

This!
I use the Fluke for measuring temps at work- I also have two lesser-known branded units from Home Depot that I have on hand for my colleagues to use....they all do a decent job at close range but the sensitivity of the Fluke to emissivity variances is lower and it works better at longer distances.
 
So... what you guys are saying is get the Kestrel AND a cheap IR thermo? :D

I'm also saying that if a precise temperature is important then using an IR therm. injects a bit of "snake oil" into the equation. The below thermograph is from an IR camera looking at regular floor tile. It was taken in mid-October on what was likely an 80 degree day. Notice the spot temp of 62 degrees. It wasn't 62 degrees in my house or outside so why so low?...because I had my front door open and the blue pattern is a reflection of the energy emitted by the upper atmosphere and at altitude the temperature is likely 30 below zero (tile is reflective even if it isn't shiny). The camera can't actually "see" the surface temp of the tile and only sees the energy emitted from it. Those emissions (in this case spot temp) are an average of the reflected energy from every heat source reflecting off the tile.

THIS is the bit of rocket science that isn't mentioned in the little book that comes with your IR thermometer. It doesn't tell you that the bullet temp you're measuring, may also be an average of your body temp and every other heat source capable of reflecting off of what you're measuring.

760-ir-3081.jpg
 
I'm also saying that if a precise temperature is important then using an IR therm. injects a bit of "snake oil" into the equation. The below thermograph is from an IR camera looking at regular floor tile. It was taken in mid-October on what was likely an 80 degree day. Notice the spot temp of 62 degrees. It wasn't 62 degrees in my house or outside so why so low?...because I had my front door open and the blue pattern is a reflection of the energy emitted by the upper atmosphere and at altitude the temperature is likely 30 below zero (tile is reflective even if it isn't shiny). The camera can't actually "see" the surface temp of the tile and only sees the energy emitted from it. Those emissions (in this case spot temp) are an average of the reflected energy from every heat source reflecting off the tile.

THIS is the bit of rocket science that isn't mentioned in the little book that comes with your IR thermometer. It doesn't tell you that the bullet temp you're measuring, may also be an average of your body temp and every other heat source capable of reflecting off of what you're measuring.

760-ir-3081.jpg

I think my best bet is to just let it come into equilibrium with the air, then use the air temp. Just by waiting for the range to go cold, unpacking my crap, setting up the chronograph et cetera it should probably be a fairly good assumption. I *could* put those stat mech classes to work, or I could just ignore all that and just see how it goes... unless there are some cheap thermocouples out there.
 
One way to get good results with your IR therm. would be to get a shoe box and line it with rags/cloth. Then cut a hole in the lid big enough for the therm. to fit in. This will block out reflections and give pretty accurate readings.
 
So... what you guys are saying is get the Kestrel AND a cheap IR thermo? :D

PDXGS, do you happen to remember which brands you dealt with? I'm thinking about going with this one: HDE® Temperature Gun Infrared Thermometer w/ Laser Sight - Amazon.com

Buddy, If you want to fine tune your settings ( DOPE ) Then Buy A Kestrel 4000/4000NV as the bare minimum or blow alot more and get any of the 4500s or the Horus/AB models, but you can get by with the 2500 or the 3500, BUT after listening to you talk you are going to want the 4000+ models because you seem to be really into the TECH side of things and thats a good thing, I'm using the 4000NV (night Vision) BUY YOUR KESTREL and if you want to mess around some more then buy your IR, Yes it will work but it will give you the BRASS Temp not the powder so you can knock about 20% OFF its Reading and that will get you closer, you will also have to Take The Chamber Temp TOO Because when you chamber the Round the Ammo Temp will Rise Too Depending how long you wait to Fire the Shot,,, So My Advise is Get Your Kestrel and that Will Fix 97% of your issues and go out and Enjoy your Rifle AND When you have learned all about that and you want to mess around more then worry about the IR,

I am sure that most of the guys/Gals Here will tell you to do this in this Order and for all of the Above, So take care and Have fun and Let the Kestrel do the Worrying for you.

Blessin's John
 
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Buddy, If you want to fine tune your settings ( DOPE ) Then Buy A Kestrel 4000/4000NV as the bare minimum or blow alot more and get any of the 4500s or the Horus/AB models, but you can get by with the 2500 or the 3500, BUT after listening to you talk you are going to want the 4000+ models because you seem to be really into the TECH side of things and thats a good thing, I'm using the 4000NV (night Vision) BUY YOUR KESTREL and if you want to mess around some more then buy your IR, Yes it will work but it will give you the BRASS Temp not the powder so you can knock about 20% OFF its Reading and that will get you closer, you will also have to Take The Chamber Temp TOO Because when you chamber the Round the Ammo Temp will Rise Too Depending how long you wait to Fire the Shot,,, So My Advise is Get Your Kestrel and that Will Fix 97% of your issues and go out and Enjoy your Rifle AND When you have learned all about that and you want to mess around more then worry about the IR,

I am sure that most of the guys/Gals Here will tell you to do this in this Order and for all of the Above, So take care and Have fun and Let the Kestrel do the Worrying for you.

Blessin's John

Done. Just grabbed the 4500NV, figured I might as well not have to upgrade for awhile anyway. If it doesn't do what I need I'll try an IR thermometer. Thanks for the great info as always guys.
 
Thermal imaging can be tricky- as mentioned, the emissivity can fool ever the best units. We used to use scotch tape with a dull finish to help with a true temp. reading....a barrel would be too hot to do this with.
A bigger effect on projectile temp is chambering a round in a hot chamber a then taking too much time to get the shot off.