Cold ammunition

[Keef]

I was shooting .22 rimfire benchrest at 100 yards today with the temperature at about -1 degree.

Has anyone noticed performance differences between warm and very cold rimfire ammo?

Maybe a reason to keep the ammo in a coat pocket?

[Jubbles]

There should be no or very little difference in all but the lowest quality ammunition.

All explosives used commercially and in the military are of a composition that reduces changes in the rate of reaction based on temperature to a minimum.

Given at any part of a week temperatures in the UK alone can vary depending on the time of the day and week from -7c to 12c (and even greater variances by month) the impact of this if POI changed as significantly as the temperature would be huge.

Will there be a POI difference between the coldest winter day and the hottest summer day, yes to a degree. Will grouping alter? Probably not.

[dances with gophers]

the only thing i can think of is the densety of the air being more dense in the cold

[Sidebyside]

Shot badly did you Keef

[shotgun sam]

The usual cry is Operator Error.

[Coldfinger]

May this is a cold barrel/warm barrel issue

[Keef]

Shot badly did you Keef

Depends on what you call "badly".

Five shots into a 0.478" group centre to centre at 100 yards is alright but there was one out of the group at 7 o'clock and on the majority of the groups I fired there was a shot out of the main group.

I was just wondering if the flyers were down to temperature but it appears not.

Some extra fine adjustment on the barrel tuner might improve it but that's an expensive game doing multiple five shot groups with Lapua Midas ammo at just shy of £12.00 for a box of fifty.

I have until the end of the month to get a group smaller than 0.430 to win the club comp!

Edit to add that the black centre is 0.625" in diameter.

[Bushdog]

I would say they were extremely good groups with a .22rf at 100 yards - my groups at that distance (albeit with sporting/varmint type rifles) are more in the region of 2" or more, not 1/2"!!

Hats off to you, but I have no idea about whether cold weather might affect performance at that level... The odd flyer seems to be a recurrent theme with .22 group size, though.

[Sidebyside]

Shot badly did you Keef

Depends on what you call "badly".

Five shots into a 0.478" group centre to centre at 100 yards is alright but there was one out of the group at 7 o'clock and on the majority of the groups I fired there was a shot out of the main group.

I was just wondering if the flyers were down to temperature but it appears not.

Some extra fine adjustment on the barrel tuner might improve it but that's an expensive game doing multiple five shot groups with Lapua Midas ammo at just shy of £12.00 for a box of fifty.

I have until the end of the month to get a group smaller than 0.430 to win the club comp!

Edit to add that the black centre is 0.625" in diameter.

I wouldn't complain at that

[flintlok]

I shoot like crap in cold weather. I could shoot good in cold weather if I ignored being wet, cold, and numb all the while bundled up and uncomfortable. I prefer being warm and toasty in winter while working on special projects such as my current project restoring a sporterized 1861 Springfield. Having said that nice shooting Keef. Now it's time to visit a warm pub.

[Keef]

[
I wouldn't complain at that

Not really complaining, on most days I would be very happy with it however I have won the centrefire benchrest comp, now I need to get my .22 group done by 0.60" to win the smallbore as well.

[Coldfinger]

I could shoot good in cold weather if I ignored being wet, cold, and numb all the while bundled up and uncomfortable.

Welcome to my world

[Deallad]

I have noticed POI change with 300 win mag at 1000 yards, my ballistic data shows a 5 moa change from cold to hot, shots land higher when hot and the air is thinner.

If there was little or no change software would not have a temperature input requirement to give the greatest accuracy.

Mike

[Cam]

I have noticed POI change with 300 win mag at 1000 yards, my ballistic data shows a 5 moa change from cold to hot, shots land higher when hot and the air is thinner.

If there was little or no change software would not have a temperature input requirement to give the greatest accuracy.

Mike

That's also my thinking on the matter.

Cam

[Shootist]

It's a competition over a year. Shoot it in the summer?