AR15 Sighting In for Long Range

[FourBee]

This has been eating at me, so I'm going to put it before you guys.
I was told this the other day by a young man who just built his 1st AR15, that sighting in a .223 AR-15 at 25 yards with standard peep sights can get you on target at 300 yards.
Now I've been shooting .223's since Vietnam, but I've never heard of that.  I've sighted in with a Scope at 25 yards for getting on paper at 100 yards, then tweaking it up on the bull.   It's fairly easy for me to get on at 200 yards, but 300 yards will seperate the amatures from the pros.  What do you all say about his statement???

[mcwoodduck]

I have my open sights on my AR sighted in for the bull at 100 yards. I am aiming at the bottom of a 10" bull so I am already 5" high at 100 from POA.  My Ar is an Armalite M15A2 standard rifle except for the rear sight only has the small appatures,  I do nto have the large combat O.  The top of the L on mine is threaded for the national match sight.
I have no problems hitting at 200 yard gongs and a slight elevation, and I have hit rocks and other items at 300 yards.  I do not have access to a range longer than 300 yards.
We are talking 2 foot bolders and I hit them.  We are not talking hitting a 2Liter soda bottle at 300 with open sights.
And I need to be off the bench with a sand bag or prone to do it.  But I think I could do it if pressed.  I have broken clay birds with hadguns off hand at 100 and 200 yards.  It takes a fre rounds to walk the bullets in but you can do it.
223 is pretty fast of a round and trajectory is pretty flat out to 300 yards.  Grab a ballistics chart.  You will be impressed at how little a 55 grain bullet will drop when sighted in at 100 yards.  Just aim that much over the target.
In the First Desert war, there were SEALS that were making hits with the standard M4 out to 500 meters,   All had sniper school.
 
 

[FourBee]

Thanks for your reply mcwoodduck:
I agree with you that a shooter can work the bullet in to the target, but to sight in at 25 yards and expect it to hit paper at 300, and with apeture sights too-boot, I can't see that happening like he says.

[FourBee]

I just got an e-mail stating that using a ballistics calculator, an M16A2 sighted in at 25 yards will hit 8" above POI at 300 yards.  At a sighting in @ 36 yards it will be on target at 300 yards.  Of course that's not figuring all the influences the weather plays.

[Gene R]

Thats standard military practice, or at least it was in the 80's. Back then they would get us sighted in at 25 yards, then we never changed our sights and qualified with them out to 300m. We weren't shooting bulls but we were shooting torso size targets. And qualifying as an expert meant hitting 37 of 40, and that was pretty damn easy with the m-16.
Ive never tried shooting bulls at 300 with the iron sights, but it sounds like your friend is pretty close to the truth. I know that with my R-15 with the Leuplod mark AR a coyote is dead at 400 yards

[mcwoodduck]

Thanks for your reply mcwoodduck:
I agree with you that a shooter can work the bullet in to the target, but to sight in at 25 yards and expect it to hit paper at 300, and with apeture sights too-boot, I can't see that happening like he says.

OH I missed that part.
I guess the size of the target matters.  I think doing it his way I could hit a Barn at 300 yards by walking it in.
I had guys walk in to my buddies gun shop and claim they are shooting a 2"  or less group at 300 to 500 yards with a standard rifle and a 4-12X 40 scope.   

[drdougrx]

Geez Mc....I wonder if it's the same guy I know that regularly states that he hits hubcaps at 700 yards with his 7mm mag and iron sights.  Why, he once regaled us of his prowess by relating the story of his gut shot doe who moved as he was aiming at her ear flicker at 400-450 yards.      Some fellers can just plain shoot!!!!

[smokehouserex]

 
 
  It's a lot easier to hit a target at long range with a keyboard than it is with a fierarm. Memories also forget group size after the fact as opposed to when it actually takes place, it is strange how measuring instruments fail to remember correctly also.  JMO
  HM

[FourBee]

A few years back I made some cardboard targets,  set'em up at 50-100-150-200-300 yards.  Then proceeded to test my rifle at those distances.  The 300 yard target still looks as good as new.

[cjclemens]

I was always under the impression that point of impact at 25 yards was fairly similar to 100 yards since the sight plane is so far above the barrel of the rifle.  The idea was that you could do a preliminary sight in at 25 yards to get in the neighborhood, and finish dialing it in at 100 later on.  I may be wrong, but thats how I learned it.

[FourBee]

I was always under the impression that point of impact at 25 yards was fairly similar to 100 yards since the sight plane is so far above the barrel of the rifle.  The idea was that you could do a preliminary sight in at 25 yards to get in the neighborhood, and finish dialing it in at 100 later on.  I may be wrong, but thats how I learned it.

That's the schooling I took.   Seems like this AR15 platform is a new ballgame altogether.  Where 25 meter zero will cross the line of sight at 25meters as the bullet rises, then drops across the line of sight again just beyond 300 meters. 

[Gene R]

Well if you sight in at 25 yards the bullet does drop it close at 100 yards, and a 55gr bullet only drops approx 11" at 300 yards when sighted in at 100 yards. So if you are shooting a torso size target you will hit it, but not the bulls eye more like the belly button but a hit is a hit and their out of the fight.
The Army didnt and dont care about bulls eyes for the average infantry soldier, only the fact he can hit a man.

[SHOOTALL]

Depending on the bullet you use , sighting in at 25 METERS will get you on target again somewhare down range on many center fire rifles with open sights. I don't know off hand the exact mesurements but it seems like between 265 yards to about 330 yards depending on round and loading. Think about what happens. Line of sight is stright where the bullet path is elevated as it leaves the bore so at some point relatively close the bullet and line of sight cross. Once down range gravity has effect on the bullet path and it will once more pass thru the line of sight.
I think most who hear of this sight in method thinks they will achive a small pin point group down range . In reality the system was developed to aquire a battle sight if troops drawing weapons only had limited space to sight in before going into battle. So at 25 meters sight in you could adjust your sights to a 100 yard zero and expect to hit a man target at 300 yards. This worked in the military because the same set up for sighting and ammo was always used . If you own a military rifle and know the ammo well you can do this . But keep in mind that the width of the front sight will be the width of a man at 300 yards ( so trying for a small group can be a real test )on alot of military rifles like the M1-A and can be used as a range finder with pratice. Appletree goes over some of this and it has been printed in "FRED'S COL." in SHOTGUN NEWS for those interested in reading about it .

[Gene R]

Shootall is right.
 
But I think most of us agree (and I've been there) that military and law enforcement firearms qualifications are substandard as far as accuracy goes. I prefer MUCH MORE accuracy out of my rifles, and out of me. But I have choices they dont have as well, when shooting 300+ yards I will be using some form of variable power optic, at least 12x. And with optics, sub-moa is the only thing I'll accept. If its not sub-moa like 1/2" or so, I slow down and change what ever or upgrade what ever or modify to do what it takes to get there. I know my rifle will group 1" at 200 yards, and coyotes cant tell when I'm off by an inch or 2, and when it stretches out to 300-400 yards on coyotes I go military...........Hit them period.. Now when shooting deer, I'm back to precision.
 
Military and most law enforcement does not have the same convienence.

[Reverend Recoil]

The best way to hit something at various ranges is to confirm and record your sight settings at those ranges.  I compete with the AR15 service rifle at 200, 300, and 600 yards.  I also practice at 100 yards.  Berger 77 gr bullets are shot at 200 and 300 yd, 82 gr. bullets are shot at 600 yd.  All shots are with a 6:00 hold on the target.  I have listed my notes from by high power rifle data book.
Range   ¼’ clicks               min of angle           target    aiming black size
100         0                              0                           SR-1       9-ring 6.35”
200         13                           3.25                        SR           9-ring 13.00”
300         23                           5.75                        SR-3       8-ring 19.00”
600         67                           16.75                     MR-1     7-ring 36.00”
Deduct one half the diameter of the aiming black for scope use and you will be on paper at these ranges.  I hope this helps.  Good luck.

[JimP.]

When i was in Army boot camp in 1971 we sighted in our M16's at 25 meters using an Army sight in target, there was a black rectangle shaped aiming point to aim at, but we zero'd the rifle using the X which was about 2.5 inches below point of aim on the target. This gave us a zero at 110 meters and the bullet was still rising and when it came down to the second zero it was suppposed to be 300 meters. This worked extremely well using the M16 and the 55 gr ammo of the time.  As you know, the Army taught us to shoot at man sized targets not bullseyes. With the rifle sighted in and using the front sight, if the target was larger than the width of the front sight, it was closer than 200 meters, if the target was smaller than the front sight, it was farther than 200 meters. cut that in half and the target was 300 meters. We aimed center mass on the target out to 300 meters and could hit it and knock it down every time. If the target was 400 meters we held the top of the front sight even with the shoulders and we would get a center mass hit, if it was 400 meters we held top of the head and would get a center mass hit, anything past that it was very iffy...  ...JimP.

[smokehouserex]

 
 
  I have never shot a M16 @ long range but if I remember correctly,,, the Navy Team, we shot M1, 10rds@ 200yds, standing/off hand,+ 10 rds. kneeling or sitting,,  up 11 clicks to 300 yds, 10rds.,,, 20 rds prone @ 600yds and that was with about 23 clicks ele.  We could take 2 sighters at each yardage.  Perfect score was 250 with 50V's,,   Nope,, I never accomplished that I usually got around 225.
  Shooting was fun and pulling targets wasn't. If you shot 235 they would issue you a M1 in 7.62 which was a little more accurate, susposedly..
 
  HM 

[ironglowjr]

if you Zero your rifle at 25 yrds it will be about 7" high at 300yrds and right on at about 375yrds......... depending on ur load of course wind and such....
 
50 yrd zero is on at 200 yrds also.....

[MSP Ret]

 
I personally prefer the 50 yard zero for my hunting AR's and other .223's as well. With the 50 yard zero you are no more than 2" above or below the line of sight from the muzzle to out to about 250 yards. Good enough for a coyote with a dead on hold if needed....<><....

[Lloyd Smale]

youll need to check your exact gun. Carry handles can vary a bit in height on non miltary spec guns and it will effect point of aim changes.