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Tempurature testing of handloads; anyone ever try this?

My Toy

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Minuteman
Oct 30, 2013
63
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People's Republic of Maryland
I saw a link (I think it was on this forum) to a small maker of ammo that was demonstrating why they used certain powders because of their lack of sensitivity to temperature extremes. The Demonstrator was obviously in a very warm climate and was demonstrating identical loads of H4895 at the current outside temperature vs. rounds he had stored in a cooler with ice that had gotten down to near freezing. His demonstration showed a very small change in velocity with that load combination.

I live in MD where it is pretty cold at the moment and still want to pursue load development. But chronographing loads and looking for pressure signs under current outside conditions only gives you part of the story. I chrono my loads at my brother's farm in PA. where he uses a wood stove to heat. My thought was to reproduce warm weather velocity and pressure signs by placing my test rounds near the stove (not on top of course, but within a safe distance checked with a thermometer and let them heat to about 95 degrees), transfer them to an insulated container and load them a couple at a time, fire them quickly and record.

Has anyone ever tried this, or is this a dumb idea?
Your thoughts.
 
Way back when the earth cooled, Kombayotch took a cooler, and oven, and a chronograph to the range.
He plotted velocity vs temperature of various powders.
He posted on line on SH and CGN.
Varget and Re17 were the first.

He has replicated some of Hodgdon's temperature stability claims for their extreme powders, and like wise for Alliant's AR-comp.

Some powder's other super powers of note that are not temp stability:
H335 and Re-17 can produce very high velocities.
CFE [Copper Fouling Eraser] can prevent some Copper fouling.

What does it all mean?
The word is out, H4350 is the bomb for hunting long range with my 7mmRemMag.
Take any bot and search the internet for H4350. It is not there. Harder to find than a $15 brick of 22 ammo.
 
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I would think that you will also need to place the firearm somewhere to get it up to temperature also. Then I wonder how much the density of the cold air outside will factor into the velocities your chronograph will display.... probably not enough to worry about I'd guess.
 
Bart Bobbitt [long time high power competitor at camp Perry] has posted on forums about how long a cartridge sits in a chamber of different temperature before it how much effect on POI.

It is measured in seconds. Most shots get off fast enough not to matter, but not all.