Chronograph and temperature.

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Axis II

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I noticed a guy at the range using a chronograph the other day and it was kind of cold outside. He is usually there on Sundays messing around so I thought maybe this Sunday with the temp being 50 degrees I would see if he would allow me to send some rounds over his chronograph. Is 50 degrees too cold or should I just buy one and wait until summer? I have a slight suspicion my best shooting load maybe a little too warm so I would like to try it and see for sure. Just worried the temp is too low and will give me a false reading. I am using h335, benchmark and h322 in 223rem.
 
Temperature should have a very small effect on an optical Chrony (mostly battery voltage and photovoltaic sensor V-rate), so the velocity measurement should be perfectly good.

Perhaps what you meant to ask is whether or not the temperature would effect the velocity. Of course, it will. How much? I guess you'll need a Chrony to answer that.

I have a slight suspicion my best shooting load maybe a little too warm. . .
And a Chrony will do absolutely nothing to answer that question. Load limits are based on peak pressure, not velocity, and individual barrels can vary 100s of fps at identical pressures.
 
The chronographs I am aware of are digital and should have relatively stable internal clocks. 50 degrees should be well inside their operating ranges so I would not think the temp would throw off their accuracy.
 
chronograph ... Is 50 degrees too cold or should I just buy one and wait until summer?
50 degrees? Heck no.

Here's member snuffy braving the freezing 32 degrees temperature to conduct chrono test for THR - https://www.thehighroad.org/index.p...ling-loaded-rounds.498890/page-3#post-6210466

index.php
 
Oh, and be prepared to hear No when you ask to shoot over his chrono. He may be willing to shoot your gun over his chrono.
My chronos have been killed twice - by other people - after being warned that the bullet exits lower than the crosshairs.
He and I were shooting 223rem together last summer and he asked if I chronographed the loads and I said no. He said he would be brining the chronograph to the club the following weekends if i wanted to check them. I never got around to it. He can shoot them over it too I have no issue with that.
 
The chronograph isn't effected by temperature. Your ammo is. But 50 degrees isn't enough to make a huge difference. Most loading manuals arrive at the published numbers at about 70 degrees. Most powder will change velocity about 2-3 fps for every degree temperature changes. So at 50 degrees you might see speeds 40-60 fps slower. At 90 degrees 40-60 fps faster.

If you're using a temperature resistant powder you'll see about 1/2 fps for each degree of temp change, so 10-15 fps slower at 50 degrees, and 10-15 fps faster at 90 degrees.
 
Agree with the others, no problems in cold temps.

My older Ohler 35P printer will print sloooowy when it's been sitting for a while in the cold, but no isues with accuracy. I've gone to the Hodgdon "extreme" line of powders for anything that will see use in summer & winter. As JMR40 said, it helps keep the temp variances down. I also make it a point to chrono loads at various temps because Strelok will infer the averages when computing data.
 
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