I was thinking differently than you I guess. I didn't intend to hit a long range... range to test temp stability. Honestly, I think it could be done at the 100yd range 11miles from my house. 3-5ea @ "room temp" and another 3-5@ ambient. Heck, here in Wyoming right now I could easily test about a 50* temp differential just by leaving the ammo in my pickup overnight.
Our low for the evening is ~24*. The house sits @ ~70* where the 2nd set of ammo would be....
Then again, I see that as a bit of an extreme. Even if I was hunting @ 20* or lower (have, many times) the ammo wouldn't be 20* at I always keep it somewhere on my body....
I'm probably overthinking... or still procrastinating.
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