How do I learn to calculate windage, elevation, etc?

[alfred10]

I am going to master an M4 this summer out to 500-600 yards. How can I get a head start learning how to calculate windage, elevation, and other variables for a colt 14.5 inch 6921 m4?

[crossgun]

I dont think your going to learn much from a 14.5 at 600 yards. Basically IMO your pissing in the wind. Wrong rifle and wrong round.

What scope are you using or are you going to shoot 600 with a red dot sight? Can you shoot 1MOA or better groups at 100 with your current set up? Dindt think so.

What are you really trying to achieve from your battle carbine?

[shootist~]

Unless you are shooting 3 MOA or smaller targets, you should be able to get hits to about 500 or so - assuming good ammo and an optic with BDC reticle; (ACOG for example), or target knobs, or even good irons. Roughly 1 MOA per 100 Yds with a 10 MPH crosswind, but actual shooting in some wind at distance is a better teacher.

Here is a link to a good online ballistic calculator you can play with.
http://www.jbmballistics.com/calculations/calculations.shtml
Everyone starts at the beginning at some point and works there way up. Enjoy the learning process.

[Paraclete comes]

Hey man glad to hear your looking to learn how to employ your rifle in all sorts of situations. Dont let all the idiots out there tell you that you cant shoot that rifle out to 500! its very do-able

so what kind of scope or sight do you have? hopefully a CQT or ACOG, S&B short dot or something magnified if not no worries. A good pair of iron sights will work just fine, but big fat red dot reticles just get messy for that range of shooting(500). dont forget any boot marine coming from basic can hit man sized targets out to 500 with iron sights. they do have an extra 1.5" on the front end but no worries bro.

if you happen to have a scope with a mil dot reticle then were in the money.

but any way here you go, go out and study the wind observe how it reacts to terrain. watch how its accelerate up will and burms, etc. take a kestrel is you have one and smoke grenades work real good.

: 0-3 mph wind hardly felt on face, 3-5 mph wind felt lightly on face, 5-8 mph keeps tree leaves in constant motion, 8-12 will raise dust and loose paper, 12-15 will cause small trees to sway, 20-25 will cause large trees to sway.

mirage-reading mirage is the primary technique used for determining wind velocity. mirage refers to the heat waves or the reflection of light through the layers of air of different temperature and density as seen by the eyes on a warm, bright day. Best seen over unbroken terrain though.

with a scope mirage can be seen on all but the coldest days with varying degrees of clarity depending on light and temp. proper reading of mirage will allow shooter to estimate and make windage corrections with a high degree of accuracy.

if you have a spotting scope read the mirage at mid to 3/4 range to the target where the wind has the most effect on the bullet. focus on the target than back off 1/4 turn or back off the scope a bit so the target is fuzzy but mirage will be clear.

mirage is very clear when reading no value wind. in this case the mirage will give the appearance of moving straight up with no lateral movement. this is called a boil. if there is any is any lateral movement of the mirage at ranges from 300 to wherever its necessary to make windage adjustments. if the waves move left to right the wind is blowing left to right. the relative speed can also be determined by the speed of the waves. EXPERIENCE will allow you to accurately determine wind velocity.

usually changes in wind speed can easily be determined by observation of mirage up to 12mph. beyond that speed the movement is to fast for the detection of minor variations. the lateral moving mirage is indicated by the heat wave becoming horizontal instead of vertical as in a boil.

keep in mind a shot can be delivered during the time mirage has changed to a boil and before it resumes to blow to the side.

oh if you have mil dots keep in mind range X wind velocity in mph div by range constant in mills = mils full wind value

okay so all that said go out and do it, take like minded buddies with you and have them out at different ranges. they can tell you the wind and you need to associate there date with your observations.

cheers