Cold weather ammo reminder

[catnthehat]

Thus topic comes up on a pretty regular basis in the winter . Some shooters pay attention to it while others do not pay particularly close attention to the rapture extremes.
Last weekend we were shooting from 600 meters to 1K,
And one of our shooters had not had his long range rifle out all Fall.
When he checked his zero at 500 and went into his log book, he found that he had to dial in 4 full MOA into hus elevation.
His load was developed in August , and we were something like -19c on Sunday.
At 100 yards on a deer one might not notice the difference , but once you get " out there" the difference is quite dramatic depending on the powder .
The powder in this case IIRC was IMR 4350 in a 260 Remington.
The elevation change on my .223 using Varget was pretty much on from a 200 "0" , to 500, to 600, less than 1MOA the first day I tried it out there.
Cat

[Twisted Canuck]

Always a good reminder Cat. There is always lots to learn and gain from here, and I always appreciate the wisdom and experience that is shared here.

[catnthehat]

The biggest take away from that range session my friend said, was the importance of taking detailed notes. So when the weather warms up he will be prepared for the elevation changes .
We were wondering just how much of a change another ten degrees warmer will make and how the plotted elevation changes with the temperature increase will look like.
It will be interesting for sure .
Cat

[Grizzly Adams1]

I'm going to say, if you're the average shooter who can't hit the broad side of a barn past 300 M, no point in worrying about it.

Grizz

[catnthehat]

Originally Posted by Grizzly Adams1

I'm going to say, if you're the average shooter who can't hit the broad side of a barn past 300 M, no point in worrying about it.

Grizz

I dunno, 4MOA can make the difference at 200 on a deer
Cat

[heretohunt]

Are you chalking this up to temperature sensitivity of the powder, or cold air’s effect on bullet travel or both?