Ballistic apps and potential energy via gravity
- Thread starter Scotchmo
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You should try to take a wingsuit up a mountain from the base, opposed to down from the mountain. 
-Matt
-Matt
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These are concepts to help you understand the effects of gravity...You literally said "Gravity act the same on both"...take it easy bud.
-Matt
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I admire the people doing that but I feel safer on the ground.You should try to take a wingsuit up a mountain from the base, opposed to down from the mountain.
-Matt
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A bicycle needs constant energy input from the rider and cannot rely on high speed momentum to get over a long hill. That is why I rather have a 1200cc 4 cylinder engine doing the work. But for now I have to wait till my wrist healed before riding again. And our yearly club rally is next weekend so I will do the boring thing of attending with a cage.
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A bicycle needs constant energy input from the rider and cannot rely on high speed momentum to get over a long hill. That is why I rather have a 1200cc 4 cylinder engine doing the work. But for now I have to wait till my wrist healed before riding again. And our yearly club rally is next weekend so I will do the boring part of attending with a cage.
To maintain a constant speed, when riding your 4 cyl engine up a hill, you need to press the gas, when you're riding it down hill, you often need to use the brakes...or coast / use far less gas. One requires far more fuel / energy than the other to travel, and the more you travel, the greater that difference becomes.
-Matt
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When started shooting FT, I went for a while out west without having to shoot an elevated target. I finally went to a match that has a lot of elevated targets and asked a very successful shooter how he dealt with the targets. He told me he used the rifleman's rule which was simply to range the base of the elevated target and use the clicks for the base distance for the elevated shot. So if a target was up in a tree....just range the base of the tree and use that distance the set clicks.
I followed that advice and missed about half of the elevated shots. I don't think the guy that told me the rifleman's rule missed any. That led me to believe that the rule was sound and I just needed practice on the elevated shots.
I dug further into the issue when I got home and realized that the rifleman's rule would actually give me the opposite correction needed on the targets that were shorter than my zero.
After this realization, I made a chart of the proper corrections and never missed another elevated shot after that due to elevation.
The weird part of the whole thing is that the guy that told me about the rule had been employing it for a tremendously long time and his hit percentage was high enough that he never considered that it was telling him the complete wrong direction to correct on his close targets.
For him, in "practical" terms...the rifleman's rule was perfectly adequate despite being completely wrong on the shorter shots.
Over time...it's an absolute certainty that he missed more elevated shots than he should have if he was correcting properly. In Scott's case...this is going to be the same. His small correction will ultimately yield a higher hit percentage regardless of his group size.
Mike
I followed that advice and missed about half of the elevated shots. I don't think the guy that told me the rifleman's rule missed any. That led me to believe that the rule was sound and I just needed practice on the elevated shots.
I dug further into the issue when I got home and realized that the rifleman's rule would actually give me the opposite correction needed on the targets that were shorter than my zero.
After this realization, I made a chart of the proper corrections and never missed another elevated shot after that due to elevation.
The weird part of the whole thing is that the guy that told me about the rule had been employing it for a tremendously long time and his hit percentage was high enough that he never considered that it was telling him the complete wrong direction to correct on his close targets.
For him, in "practical" terms...the rifleman's rule was perfectly adequate despite being completely wrong on the shorter shots.
Over time...it's an absolute certainty that he missed more elevated shots than he should have if he was correcting properly. In Scott's case...this is going to be the same. His small correction will ultimately yield a higher hit percentage regardless of his group size.
Mike
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IMO, nothing is more superior than a very experienced shooter with dope cards made from said experience in a fairly constant environment, however, in real world practices, we face environmental changes from one shooting session to another, to where, either the shooter must have a great sense of these variables and how to adjust to them, or you must rely on some ballistic / trajectory software to make the compensations for you. One rule may apply at distance A for shooter A, but not for distance B, C, or D for shooter B.
The best ballistic software to date takes into account all the factors OP brought to light, and far more. The further your shot from muzzle to target, the more variables you introduce. However, I am unaware of any ballistic software that allows inputs for multiple wind conditions (ie 5mph from 0-30 yards 3'oclock, 4 mph wind 30-60 5'oclock, ect), updrafts...downdrafts, swirls, because that is complicated as heck, and only shooting in the conditions and making adjustments on the fly, hoping those conditions remain, or repeat in the time frame of your next shot, is your only hope.
You may be presented with 5 mph winds that shoot up to 10-15 mph in relatively repeatable intervals over a long period of observation, if you time your shot right, and calculate for the 5 mph winds, you'll likely be on target, however, calculate for 5mph winds and shoot during the 15 mph gust interval, or the interval changes and happens to present itself during your bullets flight, you're gonna miss or be off to a degree, am sure BR competitors know all to well about timing the wind intervals to their best ability.
You ever notice during a walk or hike, without change in elevation, a sudden massive temperature drop, that returns to normal once you exit that location, I'm talking just 5-10 feet of distance, micro-climates exist and can present themselves in your trajectory, including heat, which will effect your point of impact, no matter how small of a degree, due to changes in air density. We don't measure the exact temperature along the entire projectile path for every shot, however in most cases this effect isn't present, but that doesn't mean it doesn't exist nor have any effect when it does.
And when it comes to a shot being off, which variable was it? Wind shift? Temp shift? An imperfect projectile? Change in muzzle velocity? Slope measured or inputted incorrectly? A little from column A and a little from column D?
The list of variables that most ballistic software does not take into account is a lot. Makes me want to go write some formulas into mine, but math is hard.
-Matt
The best ballistic software to date takes into account all the factors OP brought to light, and far more. The further your shot from muzzle to target, the more variables you introduce. However, I am unaware of any ballistic software that allows inputs for multiple wind conditions (ie 5mph from 0-30 yards 3'oclock, 4 mph wind 30-60 5'oclock, ect), updrafts...downdrafts, swirls, because that is complicated as heck, and only shooting in the conditions and making adjustments on the fly, hoping those conditions remain, or repeat in the time frame of your next shot, is your only hope.
You may be presented with 5 mph winds that shoot up to 10-15 mph in relatively repeatable intervals over a long period of observation, if you time your shot right, and calculate for the 5 mph winds, you'll likely be on target, however, calculate for 5mph winds and shoot during the 15 mph gust interval, or the interval changes and happens to present itself during your bullets flight, you're gonna miss or be off to a degree, am sure BR competitors know all to well about timing the wind intervals to their best ability.
You ever notice during a walk or hike, without change in elevation, a sudden massive temperature drop, that returns to normal once you exit that location, I'm talking just 5-10 feet of distance, micro-climates exist and can present themselves in your trajectory, including heat, which will effect your point of impact, no matter how small of a degree, due to changes in air density. We don't measure the exact temperature along the entire projectile path for every shot, however in most cases this effect isn't present, but that doesn't mean it doesn't exist nor have any effect when it does.
And when it comes to a shot being off, which variable was it? Wind shift? Temp shift? An imperfect projectile? Change in muzzle velocity? Slope measured or inputted incorrectly? A little from column A and a little from column D?
The list of variables that most ballistic software does not take into account is a lot. Makes me want to go write some formulas into mine, but math is hard.
-Matt
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Jip. If you take the above shot, 550 meter, with a smaller caliber 5.5mm and a slug with bc of .118 over flat surface at 1040fps, the maximum trajectory hight will be about 8 meter. Only that will bring a lot of different conditions like wind from any 3D direction, temperature and density changes. Like you mentioned, to many condition changes to observe.
That is why a professional sniper course doesn't take only a week. After years of training they still need to serve under a experienced senior who is doing the calls.
That is why a professional sniper course doesn't take only a week. After years of training they still need to serve under a experienced senior who is doing the calls.
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Interesting read regarding Mike's remarks on the Rifleman Rule.
en.wikipedia.org
-Matt
Rifleman's rule - Wikipedia
-Matt
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I’m
sin(15 degrees) = 0.259
That is significant.
That angle (15 degrees) and distance (600yds) is what we encountered at 2024 RMAC. The 12” plate only gives a 1moa allowance in vertical or horizontal deviation from the POA.
When extrapolating the .38” at 200yds to get to 600yds, it’s more likely a squared function. So from the .38” at 200yds, I would estimate about 3.4” at 600yds. When trying to hit a 12” plate, a 3.4” error is significant. If the dope had been correct, a 1moa vertical deviation would just clip the edge of the 12” plate. Throw in a 3.4” vertical error and now some of those shots will be off the edge of the 12” plate.
15 degrees has about 26% of the affect when compared to shooting vertically up or down.
sin(15 degrees) = 0.259
That is significant.
That angle (15 degrees) and distance (600yds) is what we encountered at 2024 RMAC. The 12” plate only gives a 1moa allowance in vertical or horizontal deviation from the POA.
When extrapolating the .38” at 200yds to get to 600yds, it’s more likely a squared function. So from the .38” at 200yds, I would estimate about 3.4” at 600yds. When trying to hit a 12” plate, a 3.4” error is significant. If the dope had been correct, a 1moa vertical deviation would just clip the edge of the 12” plate. Throw in a 3.4” vertical error and now some of those shots will be off the edge of the 12” plate.
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That is something different, and it is taken into account by most all ballistic apps.Interesting read regarding Mike's remarks on the Rifleman Rule.
Rifleman's rule - Wikipedia
-Matt
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I was referring to Mike's comments and just adding onto it for anyone interested on that subject matter...I literally stated that in the above reply you quoted...
-Matt
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I did a few shots today up a 7 degree incline and a few down a 16 degree decline. In both cases I used my Labradar but only got decent data out to about 50yds. The thought was that the projectile will lose more velocity when shooting uphill as opposed to down hill. Did not see any pattern of that from the limited data.
50yds is too short for that test. I’ll call that test inconclusive for now. The only way I’ll know if it matters is if my shots average a little low for the far uphill shots. And average high for the far downhill shots.
50yds is too short for that test. I’ll call that test inconclusive for now. The only way I’ll know if it matters is if my shots average a little low for the far uphill shots. And average high for the far downhill shots.
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At 500 yards Hornady app calculates .05 MOA difference, at 50 yards, 0 MOA difference. This is with a 338 cal 185 gr CX bullet at unknown muzzle velocity because I don't see where to input that and am too busy atm to look around and change it.
Obviously your ammo will respond much differently but I think the effect is far too small to be significant under 200yd.
-Matt
Obviously your ammo will respond much differently but I think the effect is far too small to be significant under 200yd.
-Matt
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Ahh found velocity, changed from 2600 down to 1000, now 500 yard = .06 MOA and 50 yard still 0 MOA.
-Matt
-Matt
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