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I have been challenged by a co-worker to hit an 8" steel plate at 880 yards with my Sig556. I have a NC Star 1.25-4x tactical mil-dot scope, and PMC 55gr. ammo.

I'm pretty sure it can be done but what do you guys think? What else could I use to make the shot... besides buying a new scope.

I know I can place ribbons along the range to get relative wind speed, half way and at the target. Plus scope out the target area with a spotting scope to find the biggest most recognizable aiming point, because I'm pretty sure I wont be able to see the plate with a 4x scope.

I have accuratly engadged targets at 800m with 55gr. 223 before, but it was a M249 SAW, and a 10-15 rounds burt each trigger pull.

What else could I do to lower my round count in hitting the target? Using my 556 of course.

Thanks,
Geardo
 

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The biggest challenge will be seeing your impacts, so you know how to adjust. If you can, get a plate in front of a big berm, and get a spotter watching the impacts, it will be a big help.

If you don't have a berm that shows impacts, you will be left wondering where your shots went, so you won't know how to correct.

Tracer ammo?
 

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Tracer is a good idea. Also some 75gr hand loads would be nice. I shoot 500yrds with them like nothing in my SIG. They hold up better to the wind. I also highly recommend a shooters app that I use on my Droid and they also have it for the iPhone. You put in all the data, bullet type, weight, elevation above sea level, distance, wind, humidity, temp, coriolis effect everything.
 

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Discussion Starter #4
Aren't tracers illegal? hahaha They would be fun though. Wouldn't they have a different trajectory than a ball round?

As for the Shooter app. I am a firm hater of anything "i". Don't know why. Sounds cool though.

This plate is on a berm and after some warm weather you can see your impacts. Hopefully next week when I go it will be good enough.

Thanks for the help guys.
 

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I agree with the heavier grain bullet if you don't reload try Hornady Tap 75 grain. I even get good results from Privi partisan 62,69 and 75 grain Boat tail Hollow points. Good luck 4 power scope is a little week for 800 yards but hey its worth a try. Just don't bet your rifle. :)
 

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Tracers are not illegal, though many clubs do not allow them, due to the danger of starting a fire.

To be clear, I'd bet against you on this one. I've shot at 900 yards using a dedicated long range bolt gun that is a Rem 700 with a 32" barrel with a NightForce 24x scope and hand loads. Accuracy is great, but if you are off paper, you are just chasing yourself by trying to fire at the four corners of the target trying to get a hit anywhere, just so you can see how to adjust.

Also, a lot of lighter 223 rounds, past about 500 - 600 yards, will become unstable as they go transonic, tumble, and go all erratic. If this happens, you won't be able to 'walk' your shot groups in since the actual impact point is pretty random, and getting a hit will just be random chance. Going to the heavier bullet will likely help you preserve downrange velocity, and avoid transonic stability issues.

Have you considered cheating? Get someone to stand several hundred yards behind you with a gong, and when they hear you shoot, they whack the gong with a hammer to make it gong. Since they are a few hundred yards behind you, but sound gets to them slower than your bullet is going, the timing ought to be about right. If they are in a direct line behind you, your ears probably won't detect that the sound came from behind, rather than in front. As long as you don't actually hit the plate and generate a double gong, I bet you could get 5 or 6 'hits' in a row before your challenger smells a rat ... you could be doing the 880 yard shot offhand, from the hip, and hit every time! It'd make a great beer story.
 

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I agree with the recommendations about the smart phone apps. They are like a sniper booklet but updateable and will calculate your ballistic performance instantly over a wide range of bullet weights, loads, distances, weather conditions, etc. The app on the iPhone was created and published by Knights Armament (http://www.hknightarmco.com/bulletflight/) so it is not just a bunch of physics and math geeks with no real-world experience doing a purely academic experiment but they also use live data and real-world experience. It also uses the phones GPS to whatever local conditions exist. The link I gave you will let you see the difference between the three levels of the app. The apps on other phones I do not know about but they are probably quality as well.

How much of a slope from the firing position will your target be? It may be prudent to invest in a rangefinder that calculates angle to give you a true distance to target.

As others said, get a better scope. You might be better off getting a single (but high) power scope. Even on quality scopes there seems to be a 'washout' or blurring when going from low to high power. The ones that don't are going to cost you a lot.

It doesn't matter much for a silhouette target at a few hundred yards but I imagine that 8" plate will be hard to spot even with a good scope. Will he allow you to paint it for contrast?
 

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At 880 using muzzle velocity at around 2760 for the 55 PMC you would need a dope of 46.75 MOA Elevation or holdover of 431 inches, wind correction of 1.85 MOA or 17.13" per mile per hour at full value. Given inherent accuracy of your rifle with PMC is probably around 2-2.5MOA, at 880 yds your average dispersion assuming you dope the wind correctly and that my values in ohio at 800ft are the same for your location for the PMC, you are looking at hitting a 17.6 inch target. And that's if you get everything correct on the first time, not to mention that I highly doubt your NCSTAR has 46.75 MOA of adjustment left in it which would leave you holding over with all the mil-dots you have. Not to mention you have to factor in a couple of inches of spin drift to the right and as was mentioned that round goes transonic in the 700yd range. Go for it. I bet you can hit in less than 20 rounds if you can see it and you have a good spotter watching shock wave for you. Good luck man and kick some ass. :)
These values are for an optic zeroed at 300yds.
 

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That BulletFlight iPhone app is absolutely fantastic!

If you don't know the ballistics coefficient of a given bullet, it will calculate it for you based on either muzzle velocity and bullet velocity at a given distance, or muzzle velocity and bullet drop at a given distance. Very handy little feature!

As stated earlier, it will use your GPS coordinates to get the elevation at your current location, as well as the weather conditions at the nearest weather monitoring station to you. You can also enter this info manually if you want maximum accuracy. You can also lay your iPhone on the top of the receiver and it will tell you the angle to target.

The iPhone app is actually the same software (ported to the iPhone) used in the ballistics computers being used in the sandbox by Military snipers. It costs about $30 or so.

http://www.knightarmco.com/bulletflight/

Good luck!
 

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WOW! :shock: Thanks for all the info and help guys!

So hey, this is what I'm going to do. The plate is painted white. My buddy says he will spot for me. He does want to see me hit the plate. I must use my current set up though. I can use different ammo, I will be going with Hornady Tap 75gr. Any other suggestions for ammo? besides hand load, I dont hand load yet. :roll:

I have not seen the "range" yet so I have no clue what it looks like. I just know it's across a draw with a cross wind in the middle some times. I guess it's his "place to go" for shooting. Just like my pit that I was rudely kicked out of by the Forrest Service on Memorial Day weekend... assholes :x

Art, I like the gong Idea. That's a good one. Though I'm not one to cheat

Digger, It's west of Lake Cavanaugh in the woods on a clear cut. not sure of it exact location yet. But he's got 100y 200y 400y 500y and 880y if I remember him correctly.

Muad'dib, I don't have an iPhone and I will never get one. Like I said before I don't like any thing "i". I can't spend anymore money on optics because I'm saving for the Geardo Carpet Ninja on the way. And part of the challenge is with the NC Star as well.

Cheney, Thanks for the math and for giving me my "hit window". That's real good to know. So once I'm within 17.6" I just keep aiming there?? :?: With PMC 55gr.

FYI, Mrs. Geardo is 14 weeks! It's the size of a lime and has a heart beat already. I couldn't stop smiling from ear to ear after I heard for the first time. :D :D I'm so proud!
 

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Geardo,

Sorry, I was not actually suggesting cheating. There is a line between cheating and a practical joke.

Cheating is deplorable, pulling a good shenanegan on someone is priceless.

Art
 

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My calculations for TAP at 880 for 1500 ft would be 35.75MOA Elevation, 1 MOA per mph at full value + around .25MOA right for spin drift, or in inches 330.5 in up, 8.8 in per mph wind at full value, +1.1 or so right for spin drift. Average dispersion should be closer to 10 or 11 inches at 880, good choice in ammo, it works very well and it should just be approaching transonic so you should be better off. And yeah when you get it in real close take a few shots rather than making corrections, you might get lucky.

Bullet Flight is the cats ass, I'll be saving for an ipod touch just for this program. I'm tired of carrying around my charts everywhere.
 

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Art, I completely said that wrong. I really didn't mean to shoot you down like that, for that I appologize. I knew what you went and it would be hilarious! :D :lol: :lol:

Cheney, 10" or 11" Is WAY better that 17" I just picked TAP because I read some of those tactical magazine and TAP was the smallest grouping on most of them.
 

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Geardo, if you can give me some data I can do the calc for you to give you and idea at least. I know you can't predict the weather etc. but I could put in some guesses along with the alt. humidity etc and get you some good info. Just let me know :wink:
 

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For example from my home in WI

75gr Hornady BTHP Match 100yrd zero
2800ft/sec
880yrds to target
look angle 10 degrees
Alt. 902 ft
temp 76 deg
wind 10 mph at 90 deg
coriolis effect (with spin drift) Lat.44.13 Azimuth 90

I get +32.9 MOA +9.6 mils +34.5 inches or +132 clicks
the bullet will arrive in 1.522 secs with 229 ft/lbs energy at 1172.7 fps

Just an example of what this app can do for you in seconds

:wink:
 
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