Ammo for Cooler Temps?

[Rolltide]

The weather in my area is finally starting to cool off and now I'm trying to figure out how to deal with the effects it's having on my ammo.

I shot a match this past weekend, where the temps were 40 degrees cooler than when I shot the same match in September...76 degrees when the match started in September versus 36 on Saturday.

I've read before about the effects of cooler temps on rimfire ammo, but hadn't really noticed it until I shot at 200 yards and immediately noticed that my preferred lot of Center-X was hitting over 1 MIL lower at 200 than at any other time I've shot at that distance.

I've never tried any of the Polar Biathlon ammo, but am considering picking some up to try in the colder temps. My last match of the season is this Saturday though, so I doubt I can get anything delivered and tested in time for the last match.

For those who've shot it, did you see better performance in cooler temps compared to other ammo you've shot previously?

I'm most concerned with the performance at 150 yards and farther.

Also, I realize that each rifle has it's own likes and dislikes when it comes to ammo, but I'm curious to hear if anyone has tried each of the available Biathlon ammo...SK Biathlon, Fiocchi Super Match Biathlon, Lapua Polar Biathlon, Lapua Biathlon Extreme and Eley Match Biathlon?

Lastly, is there a particular round that you've had great performance from, in colder temps that isn't a Biathlon round?

Since I'll have to order the ammo to try it out, I'd like to narrow the field as much as possible before placing an order.

For reference, the rifles I shoot matches most with, are Vudoo's, a 1727 Trainer and a 54.18 MSR.

Thanks in advance!

 

[natdscott]

My issue in temps below ~40 is that my 54.18 does not keep sub all of the great ammo that it does in the summer months.

Incidentally though, despite what the internet says, it still shoots damn near MOA at 200 yards, even with the Eley Match going briefly super.

Good ammo, that.

 

[RTH1800]

OP,
The change you describe seems excessive. I suspect other factors are at work. First thing I would do is chronograph you ammo and see what the velocity change is. Good luck.

 

[Rolltide]

OP,
The change you describe seems excessive. I suspect other factors are at work. First thing I would do is chronograph you ammo and see what the velocity change is. Good luck.

I've thought about this quite a bit and I believe the wind may have been wreaking havoc and I missed it...

 

[shaun1826]

I shot from 140 out to 220 when the temp was 82 degrees then shot 2 weeks later at 65 degrees. Below is the dope. SK rifle match. This was only a 17 degree change in temp.

82 degrees
Yds/mils
140 3.7
160 4.7
180 5.7
200 6.8
220 7.9

65 degrees
Yds/mils
140 3.9
160 4.8
180 6.0
200 7.2
220 8.4