Question 22 Ammo and Speeds / Performance with Higher Humidity

[dusterdave173]

Just asking
We shoot ARA 50 yard--early in the season I had several lots of Center X that were winning--when we crossed into the summer temps and Much higher humidity those lot numbers all got faster by a good bit and would not shoot like they had been--lots I had of much faster ammo like Polar Biathlon, Long Range etc started doing better in the very high humidity we are experiencing like 85% to high 90's Temp was mid 90's today but humidity was down around 60% and the Center X lots perked right back up and did well in testing today
Am I seeing what it looks like I am ? In the cooler early year the rifle loved lower speed stuff 1070 ish was the sweet spot and now in this crazy summer weather ammo that is chronoing very fast and doing good- is the Long Range , Polar etc 1130 ish
The Center x has jumped to mid 1090's but seems to just hate the very high humidity
Last match I shot 3 lots of center x during practice--all had been winning but they all did poor--slapped in some Polar Biathlon that was 1130 range and pulled it out of the fire with a win--That Polar had not been happy in the cool

So big match this Sat I plan on taking 5-6 lots and letting the ammo tell me what wants to shoot That day. Am I thinking right or is something else going on ??

FWIW I have really got my game together with cleaning, set up etc the season has been going Very well but now I find myself chasing a lot that will perform harder than I ever have had to

Thanks for input and ideas

 

[Straightshooter1]

Just asking
We shoot ARA 50 yard--early in the season I had several lots of Center X that were winning--when we crossed into the summer temps and Much higher humidity those lot numbers all got faster by a good bit and would not shoot like they had been--lots I had of much faster ammo like Polar Biathlon, Long Range etc started doing better in the very high humidity we are experiencing like 85% to high 90's Temp was mid 90's today but humidity was down around 60% and the Center X lots perked right back up and did well in testing today
Am I seeing what it looks like I am ? In the cooler early year the rifle loved lower speed stuff 1070 ish was the sweet spot and now in this crazy summer weather ammo that is chronoing very fast and doing good- is the Long Range , Polar etc 1130 ish
The Center x has jumped to mid 1090's but seems to just hate the very high humidity
Last match I shot 3 lots of center x during practice--all had been winning but they all did poor--slapped in some Polar Biathlon that was 1130 range and pulled it out of the fire with a win--That Polar had not been happy in the cool

So big match this Sat I plan on taking 5-6 lots and letting the ammo tell me what wants to shoot That day. Am I thinking right or is something else going on ??

FWIW I have really got my game together with cleaning, set up etc the season has been going Very well but now I find myself chasing a lot that will perform harder than I ever have had to

Thanks for input and ideas

Changes in humidity isn't going to effect MV like that, but changes in temperatures sure will. Changes in temperature not only effects the burn of the powder and also changes how the lube on the bullets work in the bore. Changes in humidity affects air density, which will have an effect down range.

 

[dusterdave173]

Ok so temp related not humidity so much
That is helpful --I suspected the humidity more but very good to know--guess I need to put my ammo in the cooler Hahaha
Thanks!!

 

[TRSR8]

Dave,
Let’s perhaps remember, when temps bump up the that much, certainly mv’s go up but also so do difficult conditions, seen and unseen. Every long term BR shooter will tell you same.
Lapua tends to be faster but the age old question….is it the ammo, is it the shooter, is it tougher condition, is it some of all?
Did you make an honest evaluation to begin with in more moderate conditions, did it suffer heat damage? All possible.

 

[dusterdave173]

Very good advice. I do protect my ammo and only take what I need for a match and am careful how it is kept. I agree with all of your ideas. I have been on a hot streak and doing very well— best I ever have have won or runner up last three matches so I have been keeping up with the wicked conditions it was just surprising how the ammo seemed to react so much. I got lulled into comfort when conditions were cooler and very similar for a couple months as ammo was very consistent and results showed that. Then as temps have soared my beloved “winning lots” started acting up
I always suspect me first but I have worked so hard to get my act together with the extra practice and attention to detail I was starting to really get results then high temps have been making keeping up a LOT harder
Thanks for the constructive comments
Learning is not easy or painless

 

[Straightshooter1]

Ok so temp related not humidity so much
That is helpful --I suspected the humidity more but very good to know--guess I need to put my ammo in the cooler Hahaha
Thanks!!

A few years ago I did just that (put ammo in a cooler) for a test I ran on Center-X, Federal UltraMatch and CCI SV's. I put dry ice in a small cooler with box of each of those in it where I measured the temperature to be at ~ 40°F (didn't have them sitting on the ice). Before I put them in the cooler to go to the range, I had them in my refrigerator over night to be sure they were cooled down. The cooler was to keep the temperature low on a day expected to be in the low 90's. So I compared the velocities and consistencies with those left out in the 90°F temperature to those in the cooler.

The UltraMatch was much more consistent at the warm temperature than the cold, as was the Center-X (g.e. UltraMatch SD: 6.0 vs 12.0 and Center-X SD: 4.7 vs 7.4). The CCI SV's were more consistent at the cold temperature than those that were warm (e.g. SD:7.7 vs 12.0). AS one would expect, the ES's were relitive to those SD's. These differences clearly showed up on paper at 50 yds. For the Center-X, I didn't see as big average velocity difference as you did within the each temperature, though there's quite a spread between the low of the cold and high of the warm. I was surprised that the CCI's were more consistent in the cooler temperature.

 

[68Hoyt]

Dave ,
Keep notes while your testing , then you will know for your rifle if humidity is affecting it
I had an issue once , I was shooting and had a rifle in the rack , it warmed up in the little bit of sun it was exposed to , it shot all over the place , I let it cool if I’m the shade and it went back to normal
And ,,,, I don’t compete , I dont keep detailed notes ( though I wish I did sometimes the grey matter isn’t what it used to be ) but I have noticed as have so many others that 22lr can change from day to day or through the day if environmental changes are considerable

 

[dusterdave173]

Thanks for the positive input

At least I have learned here that temp is the culprit not so much the humidity--the thinking about exit timing changes makes good sense so...

I am thinking I can beat it by testing several lots before the match and zero in on one that is Ok with conditions of the day--so far that seems to be working--will report after the next one.

Competing with a 22LR is a mental health stress test Hahaha

 

[foxguy]

Being a Michigander, I have noticed that shooting in 40 degree weather and 70 degree weather that I had to adjust the tuner for the temperature change. I had to adjust the tuner in a little bit for the warmer temperatures. I need a good windless day to test it at 90 degrees now.

 

[CharlieNC]

The "experts" I've talked to indicate both temperature and/or humidity can cause unusual performance. As noted keep good records to sort it out for your situation, also record the scope adjustment required to zero.

 

[243winxb]

Google- AI Overview

Higher humidity leads to lower air density, which can cause a bullet to travel slightly faster and potentially impact the target slightly higher.

 

[xswanted]

Just asking
We shoot ARA 50 yard--early in the season I had several lots of Center X that were winning--when we crossed into the summer temps and Much higher humidity those lot numbers all got faster by a good bit and would not shoot like they had been--lots I had of much faster ammo like Polar Biathlon, Long Range etc started doing better in the very high humidity we are experiencing like 85% to high 90's Temp was mid 90's today but humidity was down around 60% and the Center X lots perked right back up and did well in testing today
Am I seeing what it looks like I am ? In the cooler early year the rifle loved lower speed stuff 1070 ish was the sweet spot and now in this crazy summer weather ammo that is chronoing very fast and doing good- is the Long Range , Polar etc 1130 ish
The Center x has jumped to mid 1090's but seems to just hate the very high humidity
Last match I shot 3 lots of center x during practice--all had been winning but they all did poor--slapped in some Polar Biathlon that was 1130 range and pulled it out of the fire with a win--That Polar had not been happy in the cool

So big match this Sat I plan on taking 5-6 lots and letting the ammo tell me what wants to shoot That day. Am I thinking right or is something else going on ??

FWIW I have really got my game together with cleaning, set up etc the season has been going Very well but now I find myself chasing a lot that will perform harder than I ever have had to

Thanks for input and ideas

I firmly believe with 22s when you experience higher humidity your ammo/gun changes performance, especially when the humidity is accompanied by higher temps.

I don’t know if it’s something with lube, or the way the barrel reacts to it but there is a change.


I recently shot a match that temps were 95 by noon and over 100 by 4pm. Data for the ammo I shoot was spot on all day. Humidity was very low.

I shot about a week later in temps that were just over 90 but very high humidity and the accuracy was not the same.

I’ve had similar experiences in the past as well.

Someone, inevitably will post, quoting this post that humidity has little to no effect on ballistics and it’s the heat or me or whatever it may be.

However, as I’ve said previously, humidity has an effect on rimfire ammo and the way it performs.

 

[Straightshooter1]

Google- AI Overview

Higher humidity leads to lower air density, which can cause a bullet to travel slightly faster and potentially impact the target slightly higher.

Yes . . . faster as it goes down range due to less drag, but not at the muzzle.

. . . .unless it's so humid that water in condensing on the interior of the bore.

 

[foxguy]

And, Yet I have shot in 65-70 degree weather with a very light rain, very little to no wind, and the rifle and ammo wanted to shoot very well shooting to the Point of Aim.