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Ballistics calculator error

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I was checking out the round ball ballistics calculator and saw something I just can't wrap my head around.
Pick a diameter (any diameter). Run the calculator with two different velocities, with a 10 mph crosswind.
The calculator shows the slower velocity shot with LESS wind drift at 100 yards.
Am I missing something?
:dunno:

https://www.ctmuzzleloaders.com/ctml_experiments/rbballistics/rbballistics.html
 
Using an older version of that round ball ballistics program I found it also does like you say it does.

I put in a .500 diameter ball, 10 mph cross wind and velocities of 1200 fps muzzle velocity and 1500 fps muzzle velocity.

It says the 1200 fps ball will drift 9.7 inches at 100 yards. The 1500 fps ball will drift 12.0 inches at 100 yards.
The time of flight for the 1200 fps is .304 seconds at 100 yards. The TOF for the 1500 fps MV ball is .267 seconds.

I agree the TOF for the higher velocity ball should be less, and it is but I also don't understand why the faster ball would drift more than the slower ball.
Logic says the longer TOF would allow the cross wind to blow the slower ball further off course.

Very curious.
 
Using an older version of that round ball ballistics program I found it also does like you say it does.

I put in a .500 diameter ball, 10 mph cross wind and velocities of 1200 fps muzzle velocity and 1500 fps muzzle velocity.

It says the 1200 fps ball will drift 9.7 inches at 100 yards. The 1500 fps ball will drift 12.0 inches at 100 yards.
The time of flight for the 1200 fps is .304 seconds at 100 yards. The TOF for the 1500 fps MV ball is .267 seconds.

I agree the TOF for the higher velocity ball should be less, and it is but I also don't understand why the faster ball would drift more than the slower ball.
Logic says the longer TOF would allow the cross wind to blow the slower ball further off course.

Very curious.

Good!
So I'm not the only one who thinks basic physics should apply here.
🤔
 
My first thoughts were the Magnus Effect but after doing some digging I believe that would only effect the elevation of the ball above or below the flight path in calm air. The elevation change, either + or -, would depend on which side the wind was coming from and clockwise or counterclockwise rotation and would be likely be insignificant.
 
I was checking out the round ball ballistics calculator and saw something I just can't wrap my head around.
Pick a diameter (any diameter). Run the calculator with two different velocities, with a 10 mph crosswind.
The calculator shows the slower velocity shot with LESS wind drift at 100 yards.
Am I missing something?
:dunno:

https://www.ctmuzzleloaders.com/ctml_experiments/rbballistics/rbballistics.html
After toying with that thing a week or so - I found MANY issues with it.
I loaded my BP stuff into Ballistic Arc - a much better choice.......
 
I tried programming the same values as Zonie with comparable results. When I added a 1700FPS velocity, there was less wind drift indicated for the higher velocity load. One “possible” explanation. When shooting rimfires, standard(low velocity) loads of 1050FPS will commonly produce lower wind drift values then the high velocity ammo(1400FPS). The reason for this is instability of the faster projectile as it passes through the sound barrier(approx 1340FPS), and when subjected to wind force. The lower the ballistic coefficient of the projectile, the more pronounced this effect. A round balls shape(BC) is much lower then any rimfire projectile. I have plugged the numbers in both my Muzzleloader Ballistic Calculator, and my Ballistic ARC(well proven for my) long range shooting with unmentionables. The results, with the s 50 cal LRB producing less wind drift at a lower velocity is identical between the two calculators.
 
I tried programming the same values as Zonie with comparable results. When I added a 1700FPS velocity, there was less wind drift indicated for the higher velocity load. One “possible” explanation. When shooting rimfires, standard(low velocity) loads of 1050FPS will commonly produce lower wind drift values then the high velocity ammo(1400FPS). The reason for this is instability of the faster projectile as it passes through the sound barrier(approx 1340FPS), and when subjected to wind force. The lower the ballistic coefficient of the projectile, the more pronounced this effect. A round balls shape(BC) is much lower then any rimfire projectile. I have plugged the numbers in both my Muzzleloader Ballistic Calculator, and my Ballistic ARC(well proven for my) long range shooting with unmentionables. The results, with the s 50 cal LRB producing less wind drift at a lower velocity is identical between the two calculators.
Something definitely weird in the program.
Just for grins, I used a .49 ball at 900 fps, 1000 fps, and at 1100 fps.
The 1000 fps "shot" had less drift than the 1100 fps.
At 900 fps, it has more drift than 1000 or 1100.
 
Traveling through the speed of sound causes a higher delay in comparison to a vacuum, which causes a higher drift. This is why .22 RF match ammo is loaded to lower than sound velocity. Also applies to our rifles when the ball passes through the sound barrier. Sounds weird, but that's the way it works.
 
Any ballistics program is just an approximation of what to expect. You ultimately will have to ACTUALLY SHOOT your gun at a range to determine how different loads perform. Can’t be done with a keyboard and a computer screen.
 
When people sat down and designed these "roundball" ballistics calculators, I wonder how much REAL WORLD actual hands-on shooting, and chronograph data taking, was used. As opposed to a lot of computer generated calculations.

Which, in my opinion, as regards to actual patched ball ballistics, leaves much to be desired as to real world practicalities.

I might be wrong (often am), but I was under the impression that ALL ballistics tables were the result of bullet/cannon ball technology from the mid-19th Century to date. And had virtually nothing to do with any form of patched ball ballistics. Which was out-of-date by the time ballistics charts were starting to be compiled.

The Lyman Black Powder Handbook was an attempt to put some data in the hands of the Renaissance muzzleloading shooters. And, there are some glaring flaws in that data, great though the attempt was.

I guess I am questioning the ability of a ballistics calculator, originally designed for pointed projectiles, that has been TWEAKED for use as a round ball calculator. Without the DECADES of extensive research from the military, the powder companies, the bullet companies, the firearms manufacturers, that is what is the FOUNDATION for all.of the ballistics calculators out on the market.

There is NO COMPILATION of comparable data on which to base a round ball calculator.

Or is there? Am I wrong? If I am, I will gladly say so.
 
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Any ballistics program is just an approximation of what to expect. You ultimately will have to ACTUALLY SHOOT your gun at a range to determine how different loads perform. Can’t be done with a keyboard and a computer screen.
More of a math curiosity at this point rather than a method to use for shooting.
Just for comparison, I used Hornady's online calculator with a .57 ball.
The wind drift on their calculator seems to split at around 950 fps. More drift below and above that number.
Just one of those things... to be taken with a large grain of salt.
 
I didn't stop to think about the effects of the sound barrier but it does make sense. I know it can play heck with target accuracy and I also knew that the .22 target ammo is loaded for sub-sonic velocities for just that reason.
While velocity doesn't make much difference in close range pistol target shooting, it can make a big difference at long ranges.
 
So. why wouldn't the sound barrier affect the path of the projectile vertically?
It seems to me that a crosswind is in effect a constant horizontal push on a projectile, not much different (in a sense) than gravity being a constant pull vertically.
As I said, it's a mathematical curiosity for me at this point.
 
Any ballistics program is just an approximation of what to expect. You ultimately will have to ACTUALLY SHOOT your gun at a range to determine how different loads perform. Can’t be done with a keyboard and a computer screen.

For most muzzleloader shooting which is typically done at much shorter ranges then the modern unmentionables, it is IMO, easier to simply develop a drop/wind chart of the noted corrections by actual shooting.

Ballistic calculators are quite accurate and can be used for long range precision work if the input variables are accurate. Additionally, the algorithms used in the calculators, whether for muzzleloaders or modern firearms are usually identical. The user inputs are different. The necessity for actually shooting is to get a confirmation for the “actual” velocity, and ballistic coefficient for the particular rifle/projectile/load. Once confirmed, drop values can be accurately determined given the proper equipment is used to determine the measurable inputs(determinants) of range, atmospheric conditions, etc. Input values for wind can be more difficult because it can vary in direction and speed over time and distance(indeterminants) . A ballistic calculator is very capable of accurately measuring the drift correction IF the input values are accurate. My “other” passion for almost as long as muzzleloading has been long range hunting and competitive shooting with the unmentionables. An excellent reference if interested: “Accuracy and Precision for Long Range Shooting”, Bryan Litz. Bryan has produced several volumes on the topic over the the years.
 
I put together the round ball calculator in question.

I used the ballistics data from the British round-nose cannon reference round (19th and early 20th Century data) as a starting point and adjusted the results to account for the lower sectional density of the round ball. The output was 'confirmed' using a chronograph measuring velocities up to 50 yards, and they seemed pretty close. I would have used longer distances, but I didn't want to shoot up my chronograph.

The equations used are basic physics, but with the British empirical data as a basis. As for the 'paradox' of a higher velocity leading to more wind drift, this is a result of the round ball characteristics. Wind blowing across the ball's path and the ball's forward velocity combine as a velocity vector which results in both a rearward and sideways 'push' whose force, at a minimum, is proportional to the square of the velocity (higher at supersonic speeds). Thus, the wind force will be greatly magnified the higher the velocity. This means the maximum sideways acceleration of the ball occurs near the muzzle. The forward velocity of a round ball drops off very rapidly, but the sideways velocity does not; this is why time of flight has such a profound effect in the wind. If the velocity of the projectile was better maintained, this effect would not happen.

Hope this explanation helps; I make no claims for the calculator other than it might be a useful starting point. As others have mentioned, there is no substitute for real-world tests using YOUR rifle.
 
I put together the round ball calculator in question.

I used the ballistics data from the British round-nose cannon reference round (19th and early 20th Century data) as a starting point and adjusted the results to account for the lower sectional density of the round ball. The output was 'confirmed' using a chronograph measuring velocities up to 50 yards, and they seemed pretty close. I would have used longer distances, but I didn't want to shoot up my chronograph.

The equations used are basic physics, but with the British empirical data as a basis. As for the 'paradox' of a higher velocity leading to more wind drift, this is a result of the round ball characteristics. Wind blowing across the ball's path and the ball's forward velocity combine as a velocity vector which results in both a rearward and sideways 'push' whose force, at a minimum, is proportional to the square of the velocity (higher at supersonic speeds). Thus, the wind force will be greatly magnified the higher the velocity. This means the maximum sideways acceleration of the ball occurs near the muzzle. The forward velocity of a round ball drops off very rapidly, but the sideways velocity does not; this is why time of flight has such a profound effect in the wind. If the velocity of the projectile was better maintained, this effect would not happen.

Hope this explanation helps; I make no claims for the calculator other than it might be a useful starting point. As others have mentioned, there is no substitute for real-world tests using YOUR rifle.

Thank you for the explanation... AND for the calculator!
 
I recently programmed my Ballistic ARC and my Muzzleloader(Shooterscalculator.com) for my 58 cal Kibler Colonial rifle at 1400FPS(chronographed) using a .09BC for the 570 LRB. Both calculators gave the same output of 5.35” of drop at 100 yards using a 50 yard zero. Shown is my 100 yard confirmation which was nuts on. My hits on steel using the calculator outputs were on target at distances tested at 150 and 200 yards. On that day there was no wind, but the wind corrections looked to be very close when I shot steel a week later in 5-7mph wind.
453BCD76-FFC2-465B-9FC5-6BBFF449F4A7.jpeg
 
I recently programmed my Ballistic ARC and my Muzzleloader(Shooterscalculator.com) for my 58 cal Kibler Colonial rifle at 1400FPS(chronographed) using a .09BC for the 570 LRB. Both calculators gave the same output of 5.35” of drop at 100 yards using a 50 yard zero. Shown is my 100 yard confirmation which was nuts on. My hits on steel using the calculator outputs were on target at distances tested at 150 and 200 yards. On that day there was no wind, but the wind corrections looked to be very close when I shot steel a week later in 5-7mph wind.
View attachment 60271

:thumb:
 
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