Ballistics calculator or chart

Knochen

Knochen

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Does anyone know of a calculator or chart for bullet drop according to barrel length, caliber, and distance from target?
 
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Ballistics perhaps the wrong term

Thanks, Ken, but that appears to be for adjusting sights on a rifle. I was just curious with increasing distance from the target with various calibers of pistols and their barrel length how much it adds to inaccuracy....and I assumed that was called bullet drop (provided anticipation of shot and other foibles are eliminated). I'm actually new to shooting and am gaining as much practice and training as I can.
 
Bench fire and zero your pistol from a solid rest (sandbags, etc.) at 25 yards. Point of aim, point of impact. See where the pistol groups. Shoot at shorter ranges and see where you hit.

-- Chuck
 
You have to know the muzzle speed of the bullet from your gun and the ballistic coefficient amd weight of the bullet to calculate external ballistics. Period.
How the bullet got going that fast is irrelevant once it leaves the barrel.

Guns and bullets vary too much to just go by the size of the barrel and type of gun, and your assumptions that all similar guns are the same are just wrong. A chronograph is the best way to find the muzzle speed of your bullet from your gun. Anything else is just guessing.
http://www.handloads.com/calc/index.html

Added: To give you a specific example of how little bullet drop matters at moderate ranges with handguns, here's a specific example: my 9mm IDPA load.
My 9mm 124 gr load at 1050fps, sighted in at 10 yards is no more than half an inch off line of sight out to about 40 yards, and less than inch and a half low at 50 yards. Bullets trajectories are parabolas, so this particular load is almost a foot low at 100 yds.
So at the max IDPA range of 35 yards, if I miss my aim point by more than half an inch, it's not bullet drop, it's the shooter.
 
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Length of the barrel doesn't affect accuracy. Quality of the barrel and the handgun do. My Ruger LCR with a 1.875 inch barrel is as accurate as my 6 inch S&W 686. It's me what can't keep em in the "A" area. Length of the barrel affects velocity. And as stated, you need a chronograph to determine that. I shoot Production USPSA. I use a 5 inch M&P Pro 9mm because it makes the velocity for USPSA minor power levels easier to meet and provides a longer sight radius making it easier to shoot faster accurately. Not because it is more accurate than the M&Ps with 4.25 inch barrels. Course it is pretty darn accurate. :D

Hornady has a ballistic calculator for both rifle and handgun. You have to describe details about the bullet and its velocity and distance it is zeroed at.. Here is the link:

Ballistics Calculator - Hornady Manufacturing, Inc

Plugging in the numbers you will find it is as OKFC05 has said.
 
All things fall at the same speed, and as soon as a bullet leaves the barrel it begins falling, so the only difference in drop is due to speed. The faster a bullet goes, the less time it has to fall. :)
 
:D Actually, the bullet, shot level, will fall to the ground exactly the same time at any weight or any velocity. The faster the bullet, the further down the road it will get before it hits the ground. :eek:
 
The reason you need the weight and ballistic coefficient is to factor in how quickly the bullet slows down. The speed is not a constant, but starts to slow as soon as the bullet leaves the barrel.
In a vacuum, where there is no air friction to slow it down, you can ignore the weight and coefficient, like on the moon---just not on Earth.
 
Yes, you are both right, but again, we are talking distances in feet not miles here.
 
Thanks, guys! I began my gun venture when I went into buy a Glock 19mm a couple of months ago, but because I went with my son who remarked that bigger is better, Springfield XDs were on sale, and the fit in the hand was so much better for me than the Glock, I walked out with an XD 45. Then after a lot of research I recently added a S&W M&Pc 40 for cc. I'm ordering a Storm Lake 9mm conversion barrel for target practice only to save on bullet cost.
With all these variables I guess I was overthinking the variances. Thanks for all your comments...I really like this forum!
 
Simple physics, almost.

On the moon, the muzzle velocity would tell us how long it takes for the bullet to reach the target, and that would be sufficient to let us calculate how far the bullet drops due to the acceleration of gravity. If air resistance causes the bullet to slow down, then we would need another way to calculate the time it takes for the bullet to reach the target. With that data, the amount of drop will be determined since, as has been stated, the acceleration of gravity will be the same for bullets of all kinds.

Just out of curiosity, how would one calculate the time needed to reach the target when air resistance is taken into account?
 
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Murraybob said:
On the moon, the muzzle velocity would tell us how long it takes for the bullet to reach the target, and that would be sufficient to let us calculate how far the bullet drops due to the acceleration of gravity. If air resistance causes the bullet to slow down, then we would need another way to calculate the time it takes for the bullet to reach the target.

Just out of curiosity, how would one calculate the time needed to reach the target when air resistance is taken into account?
Click to expand...

Good question, and the answer also applies to any accelerated system operating in a gravity field, such as a rocket lifting off from Cape Canaveral, which becomes lighter as it burns off its fuel.

The answer is calculus. In the case of the bullets, we have one acceleration, gravity, which is a constant, and another acceleration, air drag, which is a function of the bullets and the square of the speed. Thus the drag on the bullet constantly changes as the bullet slows down. Twice as much speed produces 4 times the drag force.

The ballistics programs do what is called iterative calculations taking small time intervals, using the drag to calculate a new speed and then calculating a new drag, which is used to calculate a new speed, and so on until the range we desire is reached. You can add in a crosswind and calculate the sidways drift at the same time in the better programs. Notice in the program I referenced, the temp and altitude are also asked, as the density of the air affects projectile motion.
The Army uses similar programs for their artillery to take a GPS location and direct fire from several batteries to achieve multiple hits on the target from different tubes arriving at the same time. With the small portable computers now in use, the artillery calculations can be made in real time instead of taking large books of ballistics tables into the field. Nearby Ft Sill is the filed artillery school for the Army, and they teach these techniques. The firepower demonstrations are very impressive, especially when multiple batteries achieve simultaneous hits on the same target.
 
My last calculus class was 28 years ago. At that time we had 9 planets and Jupiter had 12 moons.

My position now is to leave all that fancy cipherin' to kids that have the time to do it, and I'll go punch some holes in targets and I bet you a dollar I'll be able to tell you long before they do how far a bullet drops at different velocities. :D

Now I get a kick out of showing those young engineers where their calculations were off and why the dang building is leaning.... :eek:
 
OKFC05 said:
Good question, and the answer also applies to any accelerated system operating in a gravity field, such as a rocket lifting off from Cape Canaveral, which becomes lighter as it burns off its fuel.

The answer is calculus. In the case of the bullets, we have one acceleration, gravity, which is a constant, and another acceleration, air drag, which is a function of the bullets and the square of the speed. Thus the drag on the bullet constantly changes as the bullet slows down. Twice as much speed produces 4 times the drag force.

The ballistics programs do what is called iterative calculations taking small time intervals, using the drag to calculate a new speed and then calculating a new drag, which is used to calculate a new speed, and so on until the range we desire is reached. You can add in a crosswind and calculate the sidways drift at the same time in the better programs. Notice in the program I referenced, the temp and altitude are also asked, as the density of the air affects projectile motion.
The Army uses similar programs for their artillery to take a GPS location and direct fire from several batteries to achieve multiple hits on the target from different tubes arriving at the same time. With the small portable computers now in use, the artillery calculations can be made in real time instead of taking large books of ballistics tables into the field. Nearby Ft Sill is the filed artillery school for the Army, and they teach these techniques. The firepower demonstrations are very impressive, especially when multiple batteries achieve simultaneous hits on the same target.
Click to expand...
Sounds like the days of 'zeroing in' are long gone. Just pull out the trusty calculator, punch a few buttons, and get a direct hit first time.
 
Murraybob said:
Sounds like the days of 'zeroing in' are long gone. Just pull out the trusty calculator, punch a few buttons, and get a direct hit first time.
Click to expand...

Some of the young ones think that way! But just miss a decimal point or forget to square a factor and you end up missing Mars with your satellite. :D
 
Lost Lake said:
Some of the young ones think that way! But just miss a decimal point or forget to square a factor and you end up missing Mars with your satellite. :D
Click to expand...
As a retired old geezer, I would be happy to get confused with a 'young one' any day.
:D
 
OKFC05 said:
Good question, and the answer also applies to any accelerated system operating in a gravity field, such as a rocket lifting off from Cape Canaveral, which becomes lighter as it burns off its fuel.

The answer is calculus. In the case of the bullets, we have one acceleration, gravity, which is a constant, and another acceleration, air drag, which is a function of the bullets and the square of the speed. Thus the drag on the bullet constantly changes as the bullet slows down. Twice as much speed produces 4 times the drag force.

The ballistics programs do what is called iterative calculations taking small time intervals, using the drag to calculate a new speed and then calculating a new drag, which is used to calculate a new speed, and so on until the range we desire is reached. You can add in a crosswind and calculate the sidways drift at the same time in the better programs. Notice in the program I referenced, the temp and altitude are also asked, as the density of the air affects projectile motion.
The Army uses similar programs for their artillery to take a GPS location and direct fire from several batteries to achieve multiple hits on the target from different tubes arriving at the same time. With the small portable computers now in use, the artillery calculations can be made in real time instead of taking large books of ballistics tables into the field. Nearby Ft Sill is the filed artillery school for the Army, and they teach these techniques. The firepower demonstrations are very impressive, especially when multiple batteries achieve simultaneous hits on the same target.
Click to expand...
Another question I have. All of this requires a distance parameter. It seems like distance can be obtained with the help of a 'spotter' who can be some established distance away from you and who can signal the angle he sees between you and the target. With the angle you see between him and the target, you have angle-side-angle, and can use the trigonometry of oblique triangles (the Law of Sines) to accurately calculate the distance from you to the target.

Is that the way it is done for artillery, or is there a simpler way?
 
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