Please Explain the Math Basics...

[DixieFreedom]

Is there a book out there that deals with external ballistics math/simplified?

I need to start at the basic of basics. I have not done any trig since high school. Should I just go get a high school trig book and review it first? I forgot all that stuff, don't really know what the heck subtends means. Milirads and Degrees, all that is trig ain't it? Other than that are trajectory calcs just basic algebra?

But for starts let me outline what I think I know.

1) you gotta know with precision the muzzle velocity of your projectile, B/C, weight.

2)You got to get a trajectory chart

3) You got to know the wind effect

4) Up and down slopes

5) Accurate distance to target

Then it all has to go to adjusting the scope or holding over or off.

Did I forget anything?

So how is all that done lightning fast in the field?

[meichele]

1st of all, the only way to shoot accuratley at long range with lightning fast abilities is to KNOW you rifle. Out to 600 yards or so (with a typical 6mm or bigger) the effects of air density by way of barometric pressure, humidity, temprature ect... unless changes are SUPER extreem, will have little effect on the trajectory of you bullet. So if you know your rifle and know your scope in conjunction with the load/rifle combo and have a laser range finder, you can make shots count fast out to 600 yards. After that, unless your a trained proffesional, or have alot of time to practice, you will need to calculate your shot based on the current air density.

There are many computer based ballistic calculators and some usable on a palm pilot that will accuratley calculate ballistics. Including wind, angled shots ect... If you demand to do the long form by way of typical math, you will need to brush up on calculus, algebra, geometry, ect...

Trust me, use the computer.

The Sierra reloading manual has the formulas in them. They also have easy formulas to figure angled shots.

Also "Understanding fire arm ballistics" by Robert Rinker is somewhat usefull in helping in some of these areas.

There are many writings on these subjects. If you need more info, let me know.

Also, it is very needed to have an accurate MV and BC. One should calculate his true MV by adding the distance betwwen the chrony and his muzzle. Army ordinance is .64 FPS for each foot between the muzzle and chrony.

A more accurate way is to use a ballistic calculator.

I think the only thing you forgot is you must know the air density. Factors include, Air temp, humidity, barrometric pressure. Also the BP changes with altitude. You should know the altitude, unless you are mesuring the BP, then the altitude is not important as it is the BP that affects bullet flight and not the altitude itself. Typicaly, the higher you go, the less the BP. All of these factors especially temp and BP have a HUGE impact on 600-1000 yard ballistics.

PS, One way I get set up quick for a feild shot is to constantly moniter your air and I keep several drop charts for a variety of conditions with me. Once my game is located, if I have limited time I use the pre made drop charts, which also have the number of clicks I need to adjust for any given yardage. Also, my drop charts are checked by field testing. Very important.

[ 01-02-2004: Message edited by: meichele ]

[Austin]

If you are a math buff like I am, check out http://www.aeroballisticsonline.com It gives you all the equations you could possibly need. I tend to use derivation methods in the calculus and the Newtonian methods seem to work rather well in predicting trajectory for any given projectile, though I am struggling to remember much of my engineering physics stuff to make it work more effectively for me! Trig is a must though to go this route so break out that Trig book and shake off the dust! [img]images/icons/grin.gif[/img]

TH

[ 01-17-2004: Message edited by: Austin ]

[ 01-17-2004: Message edited by: Austin ]