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?

[marky_mark]

Originally Posted by heretohunt

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

IMR 4350 isnt as temp stable as a lot of newer powders.

[CNP]

Originally Posted by heretohunt

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

Temp sensitivity for the most part. Reloader 22 is very temperature sensitive.

First example is 9 degrees C. Second example is -20 degrees C.

1. 25.06 117gr SBT 50.0 GR Reloader 22 bullet speed 2930 fps at +9C

2. 25.06 117gr SBT 50.0 GR Reloader 22 bullet speed 2785 fps at -20C

[catnthehat]

Originally Posted by heretohunt

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

Powder sensitivity .
My Varget loads in my .223 were very stable as far as POI from fall to deep winter temperatures go.

Cat

[AltaBorn]

.... Varget ....

.... ..




Plz come back to us by the truck loads.. and at great prices too..

[catnthehat]

Originally Posted by AltaBorn

.... Varget ....

.... ..




Plz come back to us by the truck loads.. and at great prices too.. :

I have relegated the last 14 pounds of Varget to my.223 and 6mmBR rifles, everything else is getting loaded with 4895 or Similar Vitvouri powders !
Cat

[tranq78]

Originally Posted by catnthehat

I have relegated the last 14 pounds of Varget to my.223 and 6mmBR rifles, everything else is getting loaded with 4895 or Similar Vitvouri powders !
Cat

I went into the pandemic with 4 pounds Varget, thought that was plenty. Have 2 left. I should have bought more.

[prarie_boy1]

Originally Posted by tranq78

I went into the pandemic with 4 pounds Varget, thought that was plenty. Have 2 left. I should have bought more.

Varget seems to be the one powder you can never have to much of. If you need something else chances are there is someone out there that will trade you for what your looking for.