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Wanted to re zero my 7Mag Encore Pro Hunter with 140gr NosPart's today,so went out to the club even though rain was predicted.

Just after I got set up it started to rain. I pondered the situation for a couple of minutes, then realized that it posed a potential problem that I have never though about before.

What effect(if any) does raindrops have on accuracy ?? Does the supersonic bullet even come in contact with a water droplet,given the shock wave it sets up during flight ??

I figure that it couldn't hurt much since I shot a 5shot group in the .6's and another barely into the .7's.(@100yds) The rain wasn't the normal downpour,however it was a steady rain with medium sized droplets.

What say ye ?? -----pruhdlr
 

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The Troll Whisperer (Moderator)
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This question was posed some time back in one of Wolfe's publications (had to be, as that's all I get anymore!) and the final answer was "little to no effect".

Not only deflection of the drop by the shock wave, but I would guess the heat of the fired projectile would help in vaporizing any liquid contact.

Watching others at a gunrange shoot standard velocity .22 LR ammo, have witnessed a vapor trail on very humid sunlight days with calm winds when viewed at a slight offset angle. Don't know it that has more to do with the shock wave, projectile heat, or a combination of both.
 

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If you take a camera and make a flash picture of falling rain to freeze the position of the drops in the air, you'll be surprised how much space there actually is between the drops. Mostly you don't hit any shooting through it, so it's hard to get effect measurements. I saw an old thread suggesting firing through a stream of water to test the idea. It's a bit more than a drop, but if you suspended a gallon water jug from a pole and put a siphon tube into it and had the glass portion of an eyedropper at the outside end of the tube, you could get a solid stream for at least a short distance before it separated into drops, and do some shooting through it to see what sort of deflection resulted? This assumes a shock wave doesn't travel up the stream and break the eyedropper? I'd like to hear about that, if it happens, too? When you do this for us, I'll be interested to hear the result? Group on paper without stream, and group on paper with bullets passing through it?
 

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I have no idea but I practice a lot from a barn window when its raining and my zero is the same or very close at nearly 300 yards with my 308.

AL
 

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Wanted to re zero my 7Mag Encore Pro Hunter with 140gr NosPart's today,so went out to the club even though rain was predicted.

Just after I got set up it started to rain. I pondered the situation for a couple of minutes, then realized that it posed a potential problem that I have never though about before.

What effect(if any) does raindrops have on accuracy ?? Does the supersonic bullet even come in contact with a water droplet,given the shock wave it sets up during flight ??

I figure that it couldn't hurt much since I shot a 5shot group in the .6's and another barely into the .7's.(@100yds) The rain wasn't the normal downpour,however it was a steady rain with medium sized droplets.

What say ye ?? -----pruhdlr


Shooting in the rain will not appreciable affect the bullets travel infact just plug in 100% humidity in a ballistic targeting soft ware and it will show no affect at normal hunting distances. Bullets creat cavitation of the air while in flight therfore the bullet never contacts the rain
 

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Hmm, not quite what you'd think. Humidity is dissolved water vapor, a gas, and it is a little lighter than air, so high humidity air is actually less dense than dry air. That's why it can rise to form clouds. I know that's counter-intuitive, but that's how it works out. In stability factor calculators increasing humidity improves stability because the air density goes down, offering less resistance to the bullet. Liquid water is another matter (literally), if you'll pardon the pun?

Cavitation is the empty space behind the bullet; a partial vacuum it pulls; literally a cavity, or empty space, in the air behind it. Hence, "cavitation", or creating a cavity. It's not something in front of the bullet that would help it with water drop impact.

That reminds me of something, though. All the talk of shock wave effect has only to do with supersonic bullets. If someone is ambitious enough and doesn't mind getting wet, run some comparisons through a water stream using both supersonic and subsonic .22 rimfire rounds. See if you can tell a difference?
 

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The Troll Whisperer (Moderator)
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Since rain or waterfalls are pretty much non-existent in my area, think I'll pass that test back to you Nick - Let you get wet! :p
 

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Is not 100% humidity rain? I've neve noticed any difference shooting rain and that is to a pretty fair distance
 

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i actually tested this, last september.
we went shooting 400 and 450 yard during a down pour.
my gosh was it raining. but we were not doing it for the purpose of testing.
we just got caught in it and since it didn't look like stopping anytime soon. (and i had it in my stuborn mind all week that, saturday i was going shooting)
we decided to set up and shoot anyway. best part was trying to affix the wet targets LOL
the result: we didn't notice any difference.
we are poor shots rain or shine LOL!!!
 

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Is not 100% humidity rain? . .
Technically, it is just air right at the dew point and unable to dissolve any additional water at all. That's why a slight drop in temperature at 100% RH, making the air unable to hold all the water it has already dissolved, causes fog. It also causes dew on any object that can nucleate droplet formation. You can also get 100% RH in rain if it lasts long enough for the air to dissolve its fill. Light rain from an isolated cloud on an otherwise dry day, may not quite get there at ground level before the rain stops again. It'll be 100% RH in the cloud itself, but not necessarily so below it.
 

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Technically, it is just air right at the dew point and unable to dissolve any additional water at all. That's why a slight drop in temperature at 100% RH, making the air unable to hold all the water it has already dissolved, causes fog. It also causes dew on any object that can nucleate droplet formation. You can also get 100% RH in rain if it lasts long enough for the air to dissolve its fill. Light rain from an isolated cloud on an otherwise dry day, may not quite get there at ground level before the rain stops again. It'll be 100% RH in the cloud itself, but not necessarily so below it.
I think you nailed it when you mentioned how far apart the drops really are. Thus the 'time' factor. Time of flight is a matter of micro seconds at close range (0-300 yds) with super sonic bullets thus the amount of contact with rain drops would be minimal and due their lack a 'mass' in relationship to the energy and momentum in the bullet would make contact with them inconsequential.
 

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Technically, it is just air right at the dew point and unable to dissolve any additional water at all. That's why a slight drop in temperature at 100% RH, making the air unable to hold all the water it has already dissolved, causes fog. It also causes dew on any object that can nucleate droplet formation. You can also get 100% RH in rain if it lasts long enough for the air to dissolve its fill. Light rain from an isolated cloud on an otherwise dry day, may not quite get there at ground level before the rain stops again. It'll be 100% RH in the cloud itself, but not necessarily so below it.

Targeting ballistics soft ware do not show any difference for rain, therefore a logical conclusion is the rain makes no differenc and that follows my experience
 

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I know this sounds ridiculous, especially looking at previous posts, but I'm sure the 20 grain .17 Remington rounds we were putting downrange one day during a downpour were fragmenting because of the rain. At 200 yards the bullet impact was...fuzzy? Almost star shaped, I guess? It wasn't a nice round hole like the other guns were putting up. I still have that milk jug somewhere...

That being said, groups seemed to open up slightly, but nothing appreciative? It wouldn't have missed you a gopher at that range, anyway. Groups seemed to be (if my tired memory serves me correctly) around 1 1/8" (at 200 yards) on a normal day with that rifle, where they were comming out around 1 1/4" to 1 3/8" in the rain.

Acutally, looking back at my post as I write it, I realized something. I wonder if this particular lot of bullets could have been shoddy? Perhaps the jackets were seperating due to a poor bond?
 
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