Room Temperature When Reloading

[Calcoyote]

Lets face it. Reloading is a precision oriented hobby. My reloading bench is out in our attached garage. Right now if you were to walk out into my garage the air temp would be approx 50 degrees. I can easily warm that up some with a space heater but all of my tools and components are going to be that temp and many metals shrink and expand with changes in temp. Will it affect my reloading consistency to reload when my dies, calipers, brass, scale, etc are cold???

 

[rayporter]

no

 

[roy22mustang]

I concur with Ray porter.
A 2.015" case at 10 degrees, will only expand to 2.0184 at 110 degrees.

That's a 100 degree swing. You said you tools are about 50 degrees, so any shooting you'd do would have about one third that variation, or about. 00114"

Is it a difference? Yes
But, answer this for me please.
Let's say you do care.

With all your tools, and components at 70 degrees, you do load development, and get the exact cartridge you want. If you shoot on an 80 degree day, the cartridge will be longer. On a 60 degree day, shorter.

Are you going to adjust your sizing die .000343" of an inch at a time, and crank out cartridges for 40, 50, 60, 70, 80 degree days? Only shoot on 70 degree days? Oh, yeah, my numbers only take into consideration the brass. You'd have to run a separate calculation for each of your tools based on the metal composition.

Here you go:

Linear Thermal Expansion

Online linear temperature expansion calculator.

www.engineeringtoolbox.com

I'm going to bet that there are other variables for you to hunt down, that will be more fruitful for you.

 

[Axlrod]

Mine was in my garage for about 5 years (then my wife let me move it into one of our spare rooms). I have loaded from -10 to about 80 above with no issues.

 

[rayporter]

benchrest shooters load outside in temps from below freezing to above a hundred.

 

[Eleven]

I’ve never worried about temps being consistent, but I do worry about relative humidity. In the summer I can have really high humidity and I will either wait for a day with lower humidity or try to be an air conditioned room that has been taking the humidity out for a while. Does it matter? I have no idea but it makes my OCD feel better.

 

[Mag_7s]

I’ve never worried about temps being consistent, but I do worry about relative humidity. In the summer I can have really high humidity and I will either wait for a day with lower humidity or try to be an air conditioned room that has been taking the humidity out for a while. Does it matter? I have no idea but it makes my OCD feel better.

Yup, your right humidity does matter. It can change your ignition and pressure pretty significantly in extreme conditions. To quote Bryan Litz "keep your powder the same amount of wet" If you are interested in this subject check out Eric Cortina's interview with Bryan on his Believe the Target channel on YouTube.

 

[Vern400]

You just don't want to reload when condensation is likely. Wouldn't want to use unvented gas heater in a cold reloading shop...that's a recipe for having issues. Temp itself is largely irrelevant, though blowing fog on reloading components couldn't be good.

 

[Matthias86]

I can't relate to the cold, but I can relate to the hot. I live in Phoenix, AZ and right now it is 115+ degrees outside right now. My setup finally took up enough space to where I had to move everything out into the garage. It is way to hot to reload any time of day right now, but I was reloading at night back in April/May. I made the rookie move of storing my powder and completed ammo in the garage as well. I was loading for my 300BLK and wanted to keep the velocity under 1100ft/s as to not break the sound barrier. I was using Accurate 1680 and other non-temp-stable powders. First round of reloads were shooting a little fast, so I removed a little powder, but shot them the following week and they were still too fast. I did this 3 weeks in a row, removing powder every time, and they all were shooting 1250ft/s. It was driving me nuts. It wasn't until I loaded one of my well tested 6mm ARC rounds and got over-pressure marks on the cases after shooting that I realized the temperature in my garage was greatly affecting my loading results. I busted out the chronograph and these rounds were going up to 250ft/s faster than I had originally recorded. Rest assured that after multiple tests, LOADING in my hot garage is fine, but STORING powder and any completed ammo in the heat is a no no. The experience helped me do more research into temp stable powders, and I learned a good lesson one how much temperature can affect performance in reloading.

 

[Rich M]

I reload in the house, garage is 90-100+ degrees and just no thanks.