Rain affecting bullets

Nice shooting Frank. I have shot a few groups like that but not many. I just sight in and its time to go hunting.

I have some loads like that or at least close to that for my 243 using Hornady 100gr bullets. Nosler 100gr bullets will shoot close to that but slightly high and left. I have to resight to use the nosler loads.

As for shooting in the rain I just don't do it. That one time at the range with the 30-06 was just a fluke. I am a fair weather shooter no two ways about it. But it was an interesting experiment.
 
You really want to see the difference or lack there of, go to a HP rifle match during a rain storm.

I've been shooting high power for nearly 40 years (started in '77). They don't call matches for rain. The only one I ever saw called was the Short Range Team Match at the Wilson Matches in '78. There was a flash flood behind the pits, they weren't worried about the shooters but didn't want the pit crew washed away.

Anyway go to the match in a rain storm. You'll notice for the good (Master-High Master) shooter's scores don't change compared to fair weather days.

The rain does effect the newer shooters, (not bullets but shooters).

The main difference is the Masters/High Masters practice in the rain and every other conditions.

The rain drops aren't gonna disrupt the bullets.
 
kraigwy wrote:
.....

The rain drops aren't gonna disrupt the bullets.

The rain does effect the newer shooters, (not bullets but shooters).
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Yep, Second that - This has been my experience, too.

Rain has not effected trajectory or accuracy for any of my rifles out to 500 yards.
 
ratshooter wrote:
...It always makes me smile when I read about guys wanting a stainless/synthetic rifle so they can hunt in the rain. Not me, if its raining I stay in camp and play cards. Contrary to popular opinion I am made out of suger and I will melt...
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But the absolute best elk hunting/stalking is in the rain,
I would say to the tune of 400% better than sunshine.
 
kilimanjaro said:
Denser air will slow the bullet and cause greater drop
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It's counterintuitive, but AFAIK humid air is less dense than dry air: A molecule of water will displace a molecule of air, and the molecular mass of water is much less than the average molecular mass of air; ergo the mass of a given volume of humid air (i.e. density) is less than the same volume of dry air.
 
It's counterintuitive, but AFAIK humid air is less dense than dry air: A molecule of water will displace a molecule of air, and the molecular mass of water is much less than the average molecular mass of air; ergo the mass of a given volume of humid air (i.e. density) is less than the same volume of dry air.
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On the other hand, there is not as much water vapor in the air as many think there is. Air that has a 68 degree dew point, (100% relative humidity @ 68F) is only about 1.7% H2O by weight.
But, yes, water vapor is less dense than air. The reason a steam locomotive's steam whistle rises in pitch as it blows is because the heavy air in the whistle's resonating tube is being replaced by steam as it sounds a note, just like inhaling helium makes you sound like Donald Duck when you try to talk.
 
Thanks for the answers guys. But I'm kinda having a hard time grasping all these formulas since rain is an uncontrollable variable.
 
First off, I've never seen a difference between shooting in the rain, and shooting on dry days. The biggest issues I've had, are long shots during the middle of summer. The "heat waves" causing refraction can play hell with seeing your target.

Rain makes up 0.2% of air volume during a 2-inches-of-rain-per-hour storm. (With 0.016 gallons of water falling through a cubic foot {7.5 gallons} of air per second.) It makes up far less than that during normal rain storms.

You have a 1:500 chance of hitting water in a one cubic foot air space (2"/hour) during a 1 second time interval.

Remember - The human brain makes us see things that are not necessarily real. It may look like a wall of water, but it's a bunch of individual rain drops. The streaking is a processing effect, done by our brains, so we have time to "see" the rain - rather than the brain only acknowledging it subconsciously.

To look at the odds of hitting water, let's look at only the bullet's path.

Imagine the bullet will travel through a "cylinder" of air.
With a .308" bullet, we need to find out how long this cylinder will be, to have a volume of one cubic foot.

1 Cubic Foot = 1,728 Cubic Inches
The volume of a cylinder is calculated as:
Pi*radius^2 (of circle)*length (of cylinder)

The radius of a .308" bullet is .154".
Pi(3.141)*.154^2 = 0.234 square inches.

1,728 cubic inches / 0.234 sq in = 7,382.5 inches

So, a .308" diameter cylinder needs to be 7,382.5 inches long to contain one cubic foot of volume. (7,382.5 inches / 12 inches per foot = 615.2 feet)

Which means.... your .308" bullet can travel 615 feet or 205 yards with a 1:500 chance of hitting water. Move closer to the target, at 100 yards; and you have a 1:1025 (0.0975%) chance of hitting water.

If it's only raining 1"/hour ... those odds go to 1:2050 (0.0488%) at 100 yards.

And that's not even figuring the adjustment for bullet flight time. Most bullets won't take a full second to reach the target. Therefore, they won't have a full second's worth of exposure, and the odds of hitting water are decreased even further.

For example (simple calculation with constant velocity):
A 2,100 fps bullet will reach a 100 yard target in 1/7 of a second (2,100 feet per second/300 feet = 1/7 second).
That means the odds of hitting water drop to a 1:7175 (0.0139%) chance of hitting water.
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the above quote is from Frankinmauser's previous post on the subject^^^

I have gotten the information in bold letters from google, the rest of the calculations are ones that I have done:

The volume of a sphere is 4/3 * 3.14 (pi) * (d/2)^3 [that last term
is the radius cubed]

So the volume of a small drop is 4/3 pi (.01)^3
= 4/3 * 3.14 * 10 ^-6 [that last term is one-millionth]
= 4.2 * 10^-6 cubic inches
And the volume of a big drop is
4/3 * 3.14 * (.1)^3 [that last term is one-thousandth]
= 4.2 * 10^-3 cubic inches
my calculations:

A 1-foot cube is 12 x 12 x 12 = 1728 cubic inches.

So it takes 1728/(4.2 * 10^-6) = 412,700,000 little drops
or
1728/(4.2 * 10^-3) = 412,700 big drops to fill the cubic
foot.

A heavy storm provides about an inch per hour of rain, so the cubic
foot is about 12 hours worth of heavy rain. this is assuming you are getting 1" and hour

Therefore the odds of filling that cubic foot with water in the time it would take the bullet to travel to the target would increase at a distance but at 100 yards, the only thing you might see is mist from a super sonic round tearing through the air and disrupting the rain drop.

These statistics would be cut in half at 200 yards etc.
 
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Thanks for the answers guys. But I'm kinda having a hard time grasping all these formulas since rain is an uncontrollable variable
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I am not being bitter in this reply, but unless it was raining in a completely straight line within the diameter of the bullet then you shouldn't have any trouble.

But GOD can do great things, so that may happen!

I do not shoot in the rain because I love my guns and want the best for my guns. I cannot bear to even see one that has been leaning up against a wall fall over 6" into the corner lol.
 
Thanks for the answers guys. But I'm kinda having a hard time grasping all these formulas since rain is an uncontrollable variable.
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Its really simple, forget all those formulas and concentrate on fundamentals and not on the rain. Fundamentals (and the bullet) is no deferent in the rain, snow or fair weather.

What will affect you is worrying about the rain and formulas instead of your shooting.
 
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