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Old 07-09-2012, 09:29 PM   #11
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I have a cabelas app that I bought for my phone it has a ballistics function and it lets you choose the brand and specific ammo and bullet gr. also have a current conditions so if the wind is blowing 15 mph it tells you how much drift and drop in inches that you will have at a particular yardage
today particular conditions o, cross wind at 15 mph and zeroed at 200 yards will have a 55.37 ft drop and a 30.2 ft drift in the cross wind at 1000 yards . at 500 drift is 72" and drop is 56.3".
at 300 21.4" drift with 8.0" drop . this is with 55 gr remington UMCs

it lets you put your zero in at what ever yardage you want out to 1000 yards , sight height , and lets you choose all your stats out to 1000 yards . it give you the current conditions where your at , wind speed, temp, barometric pressure, relative humidity , and altitude .

Im sure its not 100% perfect but I can tell you its pretty close out to 400 for sure, I dont have any where around here to go any further without shooting across a road



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Old 07-09-2012, 09:46 PM   #12
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Sniping is not all about ballistics. A good trainer can teach anyone to shoot well. The art of concealment, the patience to wait for hours or days, the ability to move as quitely as a cat, the mental ability to explode the head of another human being while you are looking in their eyes are some of the tougher parts.

Laying in the mud, with every imaginable insect sucking your blood, hungry, thirsty and with people trying to kill you, is a lot different from playing sniper in the airconditiond comfort of your computer room. It is also quite different than sitting at a bench, under cover, and plinking at steel targets at some fantastic range, knowing that in an hour and a half you are gone to a cold beer and a warm woman.



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Old 07-10-2012, 02:44 AM   #13
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I'm guessing you are younger and new to the sport but be careful using a game as your foundation for knowledge it isn't always a good idea.

Quote:
Originally Posted by Craig_Junior View Post
... I prefer the Mildots, cause every dot in elevation stands for 50 yards. Dead center in the crosshairs is 100 yards. The dots that go down the crosshairs means a longer shot, and every mil-dot reads from 100 yards, to 150, then 200, and so on. However, going up means shorter distance, which means 100 to 50, and finally 0....
I think the game is using a mildot like a ballistic drop and it isn't really designed that way. The mildot markings on the reticle are not meant correspond with a particular distance from the shooter but rather indicate the angular measurement at a distance in order to calculate the distance to a target (knowing the approx size of the target).
1 mil (short for milliradian) is the space between the dots and indicates approximately 3.6 inches at 100 yds (7.2"@200 yds and so on).
The human torso (waist to head) is approximately 36 inches so if you look at the figure of a man and his upper body takes up 2 mils in the reticle then he is approximately 500 yds out (1000/36 x target height / number of mils). Then you use the specific drop for your bullet, which you get from your "dope" (Data Of Previous Engagement) card, adjust the elevation dial or hold over using the mildots on the reticle and fire.


Quote:
Originally Posted by Craig_Junior View Post
...As for windage, I came up with this trick to help me out. Any Hunter or Sniper is going to have more than a scoped rifle, excluding a possible Spotter, it's common sense. They'll need tools of their own, and I came up with an idea to keep track of windage... A Windage Dial, basically a small fan that rotates as the wind passes through, it indicates what direction and speed the wind is going. However, in keeping track of windage on the horizontal portion on the crosshairs, that even trickier from my understanding, since I don't know how to measure wind with mildots. You'll have to calculate speed and direction of windage, as well as the movement of your target. However, windage is perplexing at first, but it's gets simpler as you get use to using the rifle and it's scope. And the idea of the Wind Dial might be a good try. However, I also learned that it's possible that Wind Dials don't exist anymore, but I might be wrong. If I'm right of them not being around, you may have to commission someone to build one for you, but that's if you want to get one; hell, I plan to get one myself.
I think you are talking about a wind meter, they are extremely common click Wind meters for examples. They can tell you the wind where you are but not at the target; you need to learn to read wind down range too (watching trees, dust, etc).



Quote:
Originally Posted by Craig_Junior View Post
Ballistics are by far the most recent and revolutionary setup for Scopes, excluding IR Scopes. Calculating windage and elevation was easier to calculate by the crosshairs design. Another thing is that Ballistic Scopes can also zoom farther, from 2 to 8 times the usual magnification. However, the idea of zooming in farther kinda perplexes me, 'cause fro my understanding, you get a clearer and closer view, but it ****s up your calculations for windage and elevation.
Ballistic drop reticles are fine if your rifle/round match what is built into the reticle. Many people still need to calculate the exact values for their rifle.
A scope with a ballistic reticle does not have any better zoom than is available for any other style of reticle. A scope with a ranging reticle (mildot, ballistic drop, etc) are built in First/Front Focal PLane (FFP) or Second Focal Plane ( SFP). With a FFP reticle the subtension (measurements) will always be correct regardless of the zoom setting. A SFP scope will only be correct at on zoom setting (usually max).

There are many great resources here and elsewhere to help you along, cheers.
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Old 07-17-2012, 11:42 AM   #14
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Quote:
Originally Posted by Chainfire
Sniping is not all about ballistics. A good trainer can teach anyone to shoot well. The art of concealment, the patience to wait for hours or days, the ability to move as quitely as a cat, the mental ability to explode the head of another human being while you are looking in their eyes are some of the tougher parts.

Laying in the mud, with every imaginable insect sucking your blood, hungry, thirsty and with people trying to kill you, is a lot different from playing sniper in the airconditiond comfort of your computer room. It is also quite different than sitting at a bench, under cover, and plinking at steel targets at some fantastic range, knowing that in an hour and a half you are gone to a cold beer and a warm woman.
Chainfire makes a good point: ballistics are probably the easiest part of being a sniper. Ballistics are a learnable science that does require a bit of art, but most of it is calculable and reproducible. The psychological stresses are what break most men that decide to leave this profession.

I remember hearing an account of a real sniper in Vietnam. He was in a hide and watching a Viet Cong soldier and was about to shoot, when he realized the VC was sitting down for lunch. He kept him in his scope for 10 minutes, waiting for him to finish his lunch. He couldn't bring himself to shoot the VC while he was hungry and eating. As soon as the VC was full and ready to get back to waging war, the sniper dropped the hammer at just over 200 meters and the VC fell dead. Every person has some problem with the hunting of other humans when it is personal. Firing a machine gun is easy compared to tracking, hunting and then shooting a person whose face you can see in your scope.
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Old 07-17-2012, 12:41 PM   #15
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Not really valid for sniper work but a fun formula to know.
Velocity squared (velocity times velocity) divided by 450240 times grain weight of bullet equals fpe (foot pounds energy)
Let's you know just how much punch you're packing.

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Old 07-19-2012, 02:29 PM   #16
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Old 07-19-2012, 04:45 PM   #17
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95,

For those of us who picked up the gun even prior to the new technology that is out that we use today. Here are some of the formulas we used.
Regarding the wind there is a different effect of each caliber.

For example one formula is for the 223/5.56 and one for the 7.62X51/308. Figured on Full value 10 MPH Wind

5.56 R x V Divided by 10 So if we were shooting at (R) 100 yrds in a (V) 10 MPH Full Value Wind the formula looks like this
The 5.56 Formula:
1 X 10 = 10 Divided by 10 = 1 MOA of Adjustment or 1 inch into the wind.
The 7.62/308 Formula is:
1 X 10 = 10 Divided by 15 = .6 MOA (we would go with 1/2 MOA or 1/2 inch.

For wind you can also use a streamer of a stick or a flag. If the flag is flying at a 40 degree angle with the flag pole you divide the degrees by "4" and that gives you the wind speed. Also it will also indicate wind direction at your fire point. But the wind may differ at a different yardage from your fire point.

The other thing is the wind. 1-3 MPH Barely feel the wind on your face. 3-5 Leaves rustle slightly. 5-8 Leaves on trees move constantly. 8-12 Dust and loose items will blow 12-15 Small trees will sway. 20-25 Large trees will begin to sway.

Then there is Full Value Wind, Half Value, Quarter Value and so forth.

With the Mil-Spec Scope we use this formula for ranging a target. It is less complicated that the original ranging formula we use to use. It is the the size of the target in inches X 27.8 Divided by the number of Mil-Dots = Actual Range to the target. There is also ranging using the standard Duplex Scope Reticles if anyone is interested we can post that also.

03

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Old 07-29-2012, 05:36 AM   #18
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the physics behind taking shots like these is that as soon as the bullet leaves the barrel, it is affected by gravity, and the path of the bullet is curved. This picture is a dramactic example of what it looks like. (Don't mind the equation).


Other factors such as wind speed and direction, temperature, and at long range in the rotation of the earth is taken in to account. That is basically the physics behind it, and all the ballistics that everyone else has listed. That's pretty much the physics, and everyone else summed up the ballistics to try and compensate for the physics. =)

This goes a little deeper in the physics stuff about projectiles
http://ipodiatry.blogspot.com/2010/03/projectile-motion.html

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Old 08-03-2012, 06:18 PM   #19
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I'm not a sniper by any means but I was a grunt in the marines and I remember this from shooting on the qual range. It gives the basic idea of wind value if you didnt understand that part.



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Old 08-06-2012, 10:47 PM   #20
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What can I teach you? I was a scout sniper in the United States Marine Corps for almost 6 years.



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