Warmer weather, do you shoot slower ammo?

[HillBillyPirate]

I have heard a few people say that when the weather warms up slower 22lr is more accurate. Wondering what everyones theory is on this.

 

[Bill K]

I shoot the same 22 long rifle rimfire rounds all year round. Never changed from what I use and have my rifle/s sighted in for.

 

[JimSC]

I don't think that I shoot with enough precision for it to matter

 

[TRSR8]

All the best is sub sonic, match grade ammo, if a good lot, shoots well hot/cold, everywhere in between.
This, in match rifles.

 

[seymour fish]

I have heard a few people say that when the weather warms up slower 22lr is more accurate. Wondering what everyones theory is on this.

Some say maintain Mach 0.92. Paradoxically some lots of fast eley at about 1175 can shoot lights out in 100 degree heat.

 

[RMcR]

Looking at our local weather forecast, our current temperature changes roughly 20 degrees through out the day. I wonder if that change in temperature of 20 degrees or so has more or less impact on the path of a bullet than monthly changes in gravity due to the tidal effect of the moon?

 

[Pawnee Bill]

I have heard a few people say that when the weather warms up slower 22lr is more accurate. Wondering what everyones theory is on this.

Sounds like more Internet wizards at work.

 

[TRSR8]

All the best ammo is sub sonic. That said, temp has nothing to do with it, everything from 1450fps-1070fps. Good ammo is good all the time.

 

[Steel Mover]

Subs are intended for social work, up close, only requirement is to be below 1,000 fps at any altitude, accuracy is in about 4th place at best on the list.

At 65 degrees and below a LR round looses at least 25 fps, below freezing over 100 fps. At 100+ degrees they gain 50 fps. Temprature has nothing to do with it....In Ft Stockton at 130 degrees, high desert, at the International Small Bore Championships I keptI my Federal Ultra Match ammo in a cooler between sets and a cold towel on my barrel. Temprature has no effect at all. Try winning a match shoot off on 22 rifle chickens at 100 with that "knowledge."

One of the biggest mistakes shooters make is not running their 22 ammo across their crono at different temperatures, and the effect at distance on accuracy and sight settings.
The Russian small bore teams have different 22 match ammo for different temperatures, especially for below freezing. The US has never developed 22 match ammo for below freezing temperatures.

 

[TRSR8]

You answered a question nobody asked, friend.
The question was about temp. related to accuracy, not chickens @ 100 yards.

 

[searcher]

Subs are intended for social work, up close, only requirement is to be below 1,000 fps at any altitude, accuracy is in about 4th place at best on the list.

At 65 degrees and below a LR round looses at least 25 fps, below freezing over 100 fps. At 100+ degrees they gain 50 fps. Temprature has nothing to do with it....In Ft Stockton at 130 degrees, high desert, at the International Small Bore Championships I keptI my Federal Ultra Match ammo in a cooler between sets and a cold towel on my barrel. Temprature has no effect at all. Try winning a match shoot off on 22 rifle chickens at 100 with that "knowledge."

One of the biggest mistakes shooters make is not running their 22 ammo across their crono at different temperatures, and the effect at distance on accuracy and sight settings.
The Russian small bore teams have different 22 match ammo for different temperatures, especially for below freezing. The US has never developed 22 match ammo for below freezing temperatures.

With that range in velocity, one would think temperature matters. If what you say about the Russians is correct - it would seem it does when at extremes. If a gun is shooting 40 FPS either faster or slower, it will take them out of the "lot range" of most precision match ammo. That is not to say their rifle still won't shoot well - but if one Lapua lot, for example, shoots better than another lot that is 30 FPSW faster or slower - there will likely be an affect on the target, however small. If velocity didn't make a difference to a rifle, we wouldn't be trying different lots of ammo (or even brands for that matter). For some disciplines - it will matter not. But for others it will - to some degree.

 

[Intell]

I hope everyone realizes that the speed marked on the ammo boxes does not correlate in any way.
I’ve chronographed ammo listed at 1049 that was actually going 1080s.
I’ve also had ammo marked 1070 to 1080 that was actually going 1040s fps.
Disregard the supposed speed. If your gun opens up through the day switch to a different lot#.
I done a lot of speed testing several years ago when Eley started printing the speed. I was amazed that there was no correlation.
If my rifle shot ammo marked 1070 fps actually at 1050 one would think 1080 ammo would shoot 1060 fps. The 20 fps does not correlate through the different speeds marked.
I found one day at a match that after my first card my ammo was opening up, marked 1080 something, I switched to a lot marked low 1040s and it came back to life. I thought “Man I’ve got this figured out!”
A few weeks later I was playing with my chronograph and discovered what I thought was a slow lot was my fastest lot and my 1080 fps was my slow lot. Some of the old gold box Lapua was as slow as 990s fps and some of the best ammo I’ve ever had. Lapua use to claim it was all 1079fps. We all know that was crap for all lots to be the same fps.
I know there are test barrels that they get an average from, but in real world testing it doesn’t hold true for me anyway.

 

[Shifty6br]

Im shooting eley club in my Hart barreled Rimx, anything beyond 100yds and eley club iIS the choice ammo for this rifle. It holds together very well at 200-300yds and I am thinking it is due to the velocity gain vs the slower standard velocities of say Sk RM which is THE choice if I want to shoot for groups @ 50yds, the eley does well but Sk is choice for this range.

That said, the Eley skirts that line between sub and super and for the most part stays sub. I have not had to adjust my zero between the seasons, nor seen any difference in accuracy, if anything I notice more occasional supersonic cracks in colder weather than warmer.

Eley Pic stamp from June 13th 2021


Eley same lot Pic stamp from Feb 6 2022


I prefer to buy in large lots, preferably 5k at a time.