Cold Weather Rimfire testing

[Tree]

I decided to take my CZ 455 16.5” barrel in a Manners stock out to see how different ammo does when it’s not warm.

Ammo tested
Federal UM22
Eley Edge
Eley Match
Eley Tenex
Lapua Midas+
Lapua Polar Biathlon
Lapua Center X

Temp 15.8 degrees, 55% humidity, 29.34 baro, 950 altitude, little wind.

Groups are at 50 yards

All ammo types followed the procedure of....

Cold barrel
10 "fouler" shots
20 Chrono
10 shot group (only 1 flyer called on the Polar was excluded from groups.)

Velocity info:
Eley Edge
Shots: 20
Min: 1066
Max: 1093
Avg: 1081
S-D: 6.8
ES: 27

Eley Match
Shots: 20
Min: 1031
Max: 1091
Avg: 1069
S-D: 11.7
ES: 60

Eley Tenex
Shots: 20
Min: 1065
Max: 1091
Avg: 1079
S-D: 5.2
ES: 26

Lapua Midas +
Shots: 20
Min: 1008
Max: 1034
Avg: 1020
S-D: 7.4
ES: 26

Lapua Center X
Shots: 20
Min: 995
Max: 1026
Avg: 1011
S-D: 9.3
ES: 31

Lapua Polar Biathlon
Shots: 20
Min: 1057
Max: 1086
Avg: 1068
S-D: 7.9
ES: 29

Federal UM22
Shots: 20
Min: 994
Max: 1056
Avg: 1027
S-D: 17.0
ES: 62

 

[straightshooter1]

Very nice Tree.

In my little temperature experiment I used Center-X , Federal Ultra Match and CCI SV's. But I not only recorded a low temperature shots, but also high temperature shots and the barrel temperature was essentially constant so that it's just the cartridge temperature difference to take into account. Also, I didn't even shoot for groups since shooter's skill tends to skew any results shown on paper.

Anyway, looking at my Center-X and Federal UM numbers compared to yours, it appears the results are in agreement in that Federal UM does NOT like to be cold as warm rounds out of the same box did much better as it normally does at warmer temperatures. And Center-X doesn't appear to be affected much.

My experiment showed CCI SV's actually improved in the cold. If you get a chance, how about doing them too and we'll see if your results with them also agree with mine???

PS: I added your data to my 22LR data base. Thanks for sharing.

 

[BlastersAreCool]

Awesome post thanks tree

 

[barronian]

@Tree what software are you using to calc/display the group sizes ?

 

[Tree]

On Android it's called range Buddy. Called something else on iOS

 

[barronian]

@Tree thanks ?

 

[billmeek]

On Android it's called range Buddy. Called something else on iOS

SubMOA Pro?