What is exact need and reasoning and HOW do you "Zero-In" a semi-automatic weapon, such an AR/15 ?

Answer 1

As there are minor differences between individual units of any mass produced firearm, including the AR-15/M-16 weapon, each weapon must have its' sights adjusted to hit the target at the desired point, hence the term "zeroing in" so that the weapon, adjusted to the individual marksman, will hit the bulls-eye, or "zero point". To "zero" a weapon, one fires groups of shots, usually 3 to 5, on a target, adjusting the sights between groups, until the weapon hits the target where you want it to.
Even though it was half worn out, my Marine Corps M-16, properly "Zeroed-In" to me, with the assistance of my Marksmanship Instructor and the incentive of my Drill Instructors, I was motivated to shoot a 239 out of 250 points, the highest score in my series (4 platoons, or 150 Marines) and earning me my first of four Marine Corps "Expert Rifleman" award badges. The last ten rounds, fired from the 500 yard line, made a group about the size of a pie plate, just left of the sternum. Finishing this event and when my Series Commander, fellow Marine Major Randall, pinned on my Expert badge, were two of the proudest moments of my life.

Answer 2

Need: So your weapon will hit where you aim.
Reasoning: A weapon that doesn't hit where you aim is not condusive to good marksmanship and doesn't inspire confidence in the shooter.
How: First, if the weapon seems to be way off target you'll need to use a large target at no greater a distance then 100 yards. If needed, you can begin the process at 50. Set your rear sight to the 100 yd range. Aim your rifle at the center of the target and fire 3-5 rounds, firing at the same point. Be sure to hold the weapon the same way each shot and take your shots slowly. (How a rifle is held will effect point of impact, which is why a rifle "zero'd" for one shooter may be slightly off for another.) Inspect the target and move the sights accordingly to move the center of your group to the center of the target. Generally, to move the point of impact to the left the windage knob will screw "down" or "tighten", if the knob is located on the right side of the rifle. If it's located on the left, The reverse is true, "unscrew" or "loosen" the knob. Also, for verticle movement, you generally screw the knob "down" or "tighten" it to move the shot group down. The reverse holds true to move your shot group up towards the center of the target. Sights vary as to how much rotation or "clicks" it takes to move the point of impact. As you become more familiar with your rifle you will begin to know how far you need to move the sight adjustment to "move" your point of impact to where you want it.
A few reminders: Your point of impact will vary slightly as your barrel heats and cools. Also, ammunition can cause your "zero" to change somewhat too. Most rifles shoot more consistantly with one brand or another of ammo. The way you hold your rifle can also effect point of impact. Try to consistantly hold your rifle in the same way each time you fire it. Eventually, you'll learn how holding it this way or that effects your point of impact. (such as on a benchrest, prone,sitting, kneeling or offhand) Each position will vary the point of impact slightly.
The last lesson for today is: There is no such thing as an accurate rifle. Rifles can only be CONSISTANT. The person shooting the firearm must be consistant too. Breath control, heartbeat, how you mount your rifle for each and every shot are all things that need to be done the same way each time to repeatedly hit the exact same spot on a target. The only thing accurate is: how well you center your target in the crosshairs. Consistantcy of your weapon and it's operator is what makes an accurate shot.

Answer 3

to zero a ar15/m16 a1 or a2 model first the front sight post must be turned up or down until the base of it is level with the base. on the rear sight it must be tuned down until it stops against the reciever then center the rear sight for windage, some have a center mark, ifnot move it all the way to one side and count the clicks all the way to the other side and divide by half as you move it back to center. fire 3 shot group at a 25 meter target, trangulate shots, adjust elevation up or down with the front sight post, windage left or right accordingly(left moves shot right and vice versa), fire 3 again, and repeat adjustments until groupings are in center of target, the rear peep sight should be on the smaller of the holes at the start. once all adjust ment are complete the weapon is now sighted in for 250 to 300 meters. if you want further than that the rear sight can now be moved up to 750- 800 meters accordingly. base zero is when you first started. info provided by u.s army and their soldier hand book and training manual

Answer 4

Because every one differs in so many way physically few very few shoot to the same settings (zero).
Because of this, every one who wants to shoot well must sight the weapon to their own needs.
To establish your own zero you need the following.

A solid bench rest with shooting bags to rest the weapon so as to make a secure foundation on which to rest you weapon while shooting.

You can forgo the bench rest and bags if none are available where you shoot, by using some form of mat to lay on and shoot from the prone position and some thing to rest the forearm ( not the barrel) of the weapon on, but I prefer prone on a mat and my Herris Bipods for it is the most accurate shooting position to set ones Zero the Bipods take the place of a shooting bag.

*** Shooting glasses and ear protection are advised***

Now what you will need is Targets to shoot at and a marker to mark all 3 to 5 shot groups so as not to get them confused once you fire a group use the marker to circle the 3 to 5 shot groups .
At 25 yards to conserve ammo fire a 3 to 5 shot group then determent which way you need to move the CENTER of the 3 to 5 shot group to get it over the center of the bulls eye of the target.
Then adjust the rear sight in the direction you need your group to move, to position it over the bulls eye.
Most modern weapons have an arrows and letters representing direction to be turned to achieve that movement to change your sight setting, R = Right and L = Left, you should find this on the right hand side of the rear sight, this will move the bullet point of impact to the left and to the right as needed (what is called windage).
Now to adjust the weapon high/low (elevation) look on the top of the rear sight you should see the letters U = UP and D = Down with arrows showing the direction to turn to achieve the desired movement to get the bullet point of impact where you wont it.
Whether your moving elevation or windage you should feel or hear clicks with each movement each click should represent ¼ of an inch of movement at 100 yards.
So base on this adjust just a little at a time to get the hang of it 3 to 5 clicks per adjustment until you are very close, then 1 to 2 clicks at a time to fine tune.
When you are on zero at 25 yards move back to 50 yards fire a 3 to 5 shot group and adjust again to assure you are still on zero when you are on zero again then move back to 100 yards and repeat the process until you are on zero again, once this is completed your done.
Have plenty of targets so you can change out as needed to avoid being confused with too many holes.
You may wonder why 25 yards then 50 then 100.
Easy the 25 is your first major adjustment, the later to ranges are for fine tuning the weapons Zero.
If at 25 yards your off zero ½ inch and don’t notice it at 100 yards you will be off several inches 2 to 3 that you will notice.
Now if you were to return to your starting point of 25 yards and fire you will see you windage (left Right) will be perfect but your elevation (High/Low) will not be the same that how you wont it.
You will be zeroed for 100 yards most shots are at 50 to 150 yards and your 100 yard zero is good for those ranges.
Sounds a little intimidating but you can handle it, and each time from then on it becomes easer.
I also attached a few links that too may help you.
Hope I was of some help

D58




http://members.aol.com/SweetAccord/Sights.htm

http://hunting.about.com/c/ht/00/07/How_Sight_Gun0962933352.htm

http://www.chuckhawks.com/sight-in_rifle.htm

http://www.abousainc.com/SightIn.htm

http://www.gunnersden.com/index.htm.sightin.html

Answer 5

Ok Rambo so you can hit something with it
Adj the sights

If your real good at stalking I guess you could just hit them over the head with it im going to another subject you people are scaring me how did you get a firearm

Answer 6

Take it to a gunsmith. They can do a better job than you could (if you are a novice at this).

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