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Old 01-05-2013, 04:54 AM   #11
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I see other posters have already given you lots of advice on ballistics data, but to answer the question as I read what you have posted, let's explain the difference between the bullet's drop and the line of sight to your target.

If you were to draw an imaginary line from the sights of your rifle to whatever you're pointing at, you would have defined the line of sight. Bullet drop is the distance between your light of sight to whatever you aimed your rifle at and the actual flight path of the bullet, which is always a vertical measure and usually a negative number except for very close to the muzzle of the rifle.

Your elevation above sea level and the ambient temperature (both affect air density) are going to have a lot more effect on the strike of the rounds on your target than a 15 degree depression at 100 yards.

Between 0 and 100 yards or so for 5.56MM NATO ammunition, there's very little difference in bullet drop except at extreme firing angles.

The question you posed is something to consider when shooting at extended distances and/or more extreme angles. Then there's lots of stuff to consider.

Hopefully my explanation didn't serve to further confuse you.
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Old 01-05-2013, 12:42 PM   #12
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Quote:
Originally Posted by fsted2a View Post
Army manual (TM 23-9) say do it at 25 meters, which equals about 30-35 yards. 50 yards should be good to go. If you do it that way, you will keep it on the paper. After that, it is more up to your marksmanship fundamentals (Breathe, Relax, Aim and Squeeze). Not knowing what your skill level was and basing your question off the title of the thread is how I based my esponse.
25 meters = 27.34 yards, just for the record.
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Old 01-05-2013, 09:19 PM   #13
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Originally Posted by treehugger49 View Post
25 meters = 27.34 yards, just for the record.
I'll buy that. I think the reason the military zero's at 25 meters is that there are a lot of folks coming through that never fired even one round of anything prior to joining, and 50 meters on a 8 1/2 x 11 paper is pushing it for some at first.
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Old 01-06-2013, 02:57 AM   #14
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Quote:
Originally Posted by fsted2a

I'll buy that. I think the reason the military zero's at 25 meters is that there are a lot of folks coming through that never fired even one round of anything prior to joining, and 50 meters on a 8 1/2 x 11 paper is pushing it for some at first.
The reason the military zeros at 25 meters is because ballistically speaking the rounds point of aim and point of impact ad the same same at both 25 meters and 300 m which is the "normal" range of fire fights in combat.
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Old 01-06-2013, 11:08 AM   #15
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The reason the military zeros at 25 meters is because ballistically speaking the rounds point of aim and point of impact ad the same same at both 25 meters and 300 m which is the "normal" range of fire fights in combat.
At least it was when the doctrine was written, which was during the cold war. From what recent engagements I have seen the AAR's on, the range is much closer in recent times. But the zero is still a good range for most troops.
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Old 01-09-2013, 05:34 AM   #16
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Quote:
Originally Posted by 2tone0311 View Post
The reason the military zeros at 25 meters is because ballistically speaking the rounds point of aim and point of impact ad the same same at both 25 meters and 300 m which is the "normal" range of fire fights in combat.
I'm still wet behind the ears with scopes and AR-15s, but if I read the chart right, the poa/poi is the same at the far end at 375y/343m. Of course it would be easier to follow the chart if Havoc would change his avatar. Please...just for the chart posts...
Are the ballistics for .223Rem substantially the same as .556 military. I'm going to be scope zeroing myself this weekend.
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Old 01-09-2013, 11:19 AM   #17
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Of course it would be easier to follow the chart if Havoc would change his avatar.

There was a ballistics chart posted? Where? I didn't see anything
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