Sniping

[backfromthefuture]

I need to know one thing, and any info would help.
I'm trying to find out how to calculate windage and
set it on your scope and everything so when the wind
is up, or its a far shot, i could get a more accuate shot?
This is one thing I never knew how to do.
I would appreciate any help.

Thanks.
BFF

[Bud Helms]

You will most definitely get some great help in the Art of the Rifle Forum. Moving there.

[Picher]

Unless you're shooting in a match and can adjust by shooting sighter shots, most people estimate hold-off for windage and elevation because it can change for every field shot.

A range finder can help with distance, but wind is more difficult to judge because it's not usually constant from the muzzle to the game or target. There are windage deflection columns in ballistic tables that can help. You can do a search on ballistics on the 'net to find them.

Generally, cross wind near the first third of the bullet's flight has more of an effect on deflection than in the last third. That's because it creates a lateral acceleration and velocity that results in distance from the line of sight that continues to increase all the way to the target.

It's a matter of physics. Distance = Rate of speed x Time travelled. You know driving 60 mph for one hour will get you 60 miles down the road. Rate of speed is a function of the (wind) force causing the acceleration and the amount of time that force is applied. That's probably more than you wanted to know, yet not enough to make a prediction on how much the bullet will be deflected by wind.

There are computer programs that can compute windage for various calibers, distance, and wind velocity.

Picher

[backfromthefuture]

Do you know of computer programs.
I could find them, but I was wondering
if you know of any that you would suggest?

Thanks again.
BFF

[texfar]

BFF, Just about all of the bullet manufacturers have a ballictics program. Sierra etc. I bought my program from Oheler Chronographs in Austin Texas When I bought my Chrono. It is called the Ballistic Explorer and works good.

[Twycross]

If you just want a free, but maybe not quite as good ballistic calculator, you might want to check out http://www.biggameinfo.com/index.asp...2fbalcalc.ascx or http://www.handloads.com/calc/index.html.

[fanoblack]

A shooter from my Hometown! Yeah, not that I have been hunting with a rifle a lot, but my Dad (and his Dad or older male relative before him) just told him to hold off. If you shoot enough thats much easier than adjusting sites. However, if target shooting is your game then holding off may not be the best idea.

fanoblack

[Zak Smith]

"OPTICS FOR PRACTICAL LONG RANGE RIFLE SHOOTING"
http://demigod.org/optics

Explains elevation and windage adjustment.

[backfromthefuture]

do any of y'all know how to calculate windage and all that manually, just like a sniper would. Say i'm hunting and I see a deer 400 yards away and can't get closer and he ain't coming any closer, and the wind is slightly blowing, how can i calculate the windage and all to enter on my sights on my rifle to take a good accurate shot? I know the marine scout/snipers do this all the time.

BFF

[root]

correct me if I'm wrong, but with a mil-dot scope and the accompanying cheatsheets you should have no trouble at all.

or you can just buy this:
http://www.horusvision.com/hv.cfm?pg=h25

[yorec]

I think the kind of caluclation you're wanting is a method of estimation... ?

I such a scenario - you need to be familiar with the tables already mentioned, so you know about what your bullet should do in a given situation. This means memorizing those table - believe it - that's one of the things those guys have stored in thier brains.

Then it's a matter of extimating how fast the wind is moving in the field between them and the target and plugging it in to what they know thier bullet will do when travelling over such a course. Calculate the range, conditions, and how things go together right and they adjust properly and hit. Wrong and they miss. Simple as that.

For deer hunters at 400 yards and in - ya still gotta be familiar with what you're bullet will do given a wind speed. You know that it will move a few inches given a set of circumstances so you aim those few inches to make up for the changes. Not all deer hunters memorize wind drift tables - many go on "instinct" which means and educated guess on how things will shape up. Many are very good at it - but some memorize tables just like the professionals.

Bottom line is you've gotta do some research on what your bullet's going to do while it travels those yards whether professional shootist or weekend backwoodsman. Find one for the caliber/bullet/velocity you shoot and get to studying. And don't forget to practice - shooting knowledge is just so much trivia unless you put practice to thought.

[30Cal]

do any of y'all know how to calculate windage and all that manually, just like a sniper would. Say i'm hunting and I see a deer 400 yards away and can't get closer and he ain't coming any closer, and the wind is slightly blowing, how can i calculate the windage and all to enter on my sights on my rifle to take a good accurate shot? I know the marine scout/snipers do this all the time.

Well, you either need some sort of personal calibration (Kentucky windage) for what "slightly blowing" is or you need to estimate/measure a speed and direction. Winds from 3 o'clock and 9 o'clock are full value. Winds from 1,2,4,5,7,8,10 and 11 o'clock are worth roughly half. I find it best to try to bracket the wind--"it's at least 4mph but not more than 7"--and use that to fudge my answer to increase my chances of a good shot.

Off the top of my head, for a 30-06/308 or similar cartridge, the answer for a full value wind (say 5mph) at 400yds works out to be about 1, maybe 1.25 MoA. (I know I need 5MoA at 600yds for a 10mph full value wind. 400yds would be about half that and to get 5mph, divide in half again).

Also, at 300+yds, you'll need to have a pretty solid range otherwise your elevation will be too far off for a good shot on medium game.

Find a copy of Sniper field manual (FM23-10). It's available free online in various forms. The data tables might not be perfect for your rifle, but they're a good starting point for most typical non-magnum, non-wildcat centerfire rifles and does a good job of giving you an idea of how to come up with good compensations. You can always find data for your particular cartridge and apply the same principles.

Ty

[30Cal]

Here ya go:
FM 23-10

[BCBR]

Try here,I am buying 2 fer Christmas.
http://www.shooterready.com/:)

[kirbymagnum]

can someone explain to me what the Ballistic Coefficient is? And what is it for a .243? Do you need to know the bullet weight?

Do all scopes adjust the same amount with one click? And what does MOA mean?

[30Cal]

BC is a measure of how quickly a bullet gives up velocity. By definition, some particular artillery projectile has a BC of 1 and everything else is measured against that. The higher the BC, the more velocity the bullet will retain downrange and the flatter the trajectory will be for a given muzzle velocity (less wind drift too).

BC will vary from bullet to bullet. They're published by manufacturers and it's not hard to track down if you know what bullet you're talking about. .35-.45 are pretty typical numbers. Some of the long range specialty bullets are up in the .5 range.

Most scopes are 1/4MoA per click. Some are 1/8, some are 1/2.

Ty

[Twycross]

The Ballistic Coefficient (BC) is essentially a measure of how easily the bullet defeats air resistance. The higher the BC, the more aerodynamic the bullet. It varies from bullet to bullet. In 7mm, a Winchester Failsafe has a BC of .384, and a Ballistic Silvertip has a BC of .420, IIRC. So the Silvertip is more aerodynamic than the Failsafe, and given the same weight and velocity, the Silvertip will have a flatter trajectory.

MOA = Minute of angle. 1 degree = 60 minutes = 60 seconds, if you remember from geometry classes. Roughly, 1 MOA equals about 1 inch at 100 yards. It's not exact, but it's a good enough approximation.

[kirbymagnum]

Can somone explain to me what the Ballistic Coefficient and MOA means. Does anyone one know the ballistic coefficients for a .243 does the bullet weight matter?

[Twycross]

Huh? 30Cal and I just answered your question. Is this a double tap, or are our answers unintelligible to you?

BTW, the bullet weight does affect the BC. You will have to know the exact bullet type and weight to find the BC. With those, you should be able to find what you want on the web.

[Blackwater OPS]

MOA = Minute of angle.

Almost. It's minute of ARC which is equal to one sixtieth (1/60) of one degree. That automatically extends to one inch at 100M. It is commonly referred to as minute of angle but arc is much more descriptive of what MOA actually represents.

[esldude]

Pointblank is good free ballistic software.
www.huntnut.com

Most ammo makers publish BC in ballistics tables on their ammo on their websites. If not, you can use pointblank and info about velocity at any two distances to calculate it for yourself.

Wind deflection is proportional, meaning 2mph has twice the effect of 1 mph. It operates as a square function (well almost) as distance increases. Meaning twice as far will give close to 4 times the deflection. So if you have some table with info for say 10 mph, you can fairly quickly figure it for most circumstances. Or better yet, print out a chart for your ammo and rifle.

[backfromthefuture]

Thanks for all of ya'lls help.

BFF

[FirstFreedom]

elsdude, that link doesn't work.

bcbr, here is your corrected link: http://www.shooterready.com/

Mr. Gew98 on this forum would have some info for you if he makes an appearance.

[Marky]

The title says it all, it will even tell you all about dialing in scops the easy way.

[DimitriS]

Its actually: http://www.huntingnut.com/ For Point Blank

Dimitri