Posted this question in the general forum before I found this area.  Any comments from other LE instructors who have run into this?


Is it common for two people to have different points of impact using the same rifle and the same sight picture? Here's the problem. Shooter one shoots the rifle just fine, standard peep sights on a carbine. Shooter two, left eye dominant shooting left handed, shoots the same rifle with his groups about 4 inches to the right at 25 yards. Make the adustment for lefty and he is right on target but now the righty is off? Any idea what is going on here? I would think that if both have the same sight picture then point of impact would be the same.

Thats a big leap to say that they are both going to have the same sight picture.  They can be holding the sights at the same spot on the target - BUT (and more important than sight picture is Sight Alignment) if Sight Alignment is even slightly different from the other, the point of impact will be different.

Hell, how many times has someone taken out their AR with ghost ring sights after not having shot it for awhile and "their sights are off"  Guarantee those sights havn't moved since the rifle was in the safe.  They are simply using a different sight alignment.  Now, apply that to two different shooters with the same rifle...well...

Not only that, if it is going right for a left left handed shooter they may be pushing on the trigger.

As a patrol rifle instructor I have found you can have different POI with different shooters.  The AR-15 is a site to shooter weapon.  With most people of the same body type and size POI could be close but you would not want to bet lives on that.  But with a cross dominate eye I would think it would be very different to the point you would not want to take a high risk shot in an LE situation to much liability.  I have picked up others rifles on the range and shot them and have had no problem hitting what I need to.  Others I have picked up I have been all over the place and it was dead on for the officer that used.
it.  

Center of mass at close ranges with a rifle someone said they sited in I would think there would be no problem still would not want to count on it in a fight. But any kind of 25 + yard shot at a specific body area you want to have the rifle sited for you.  Also close range head shots where mechanical offset starts to play a roll you want it sited for you.

Just my opinion, hope it helps.

P099

I agree, variations in sight alignment, how the rifle is being held and operated.   This is why evry rifle in the military gets zeroed for the operator that the rifle is assigned to.   As far as law enforcement at my department we have fleet vehicles with fleet rifles in the vehicles, everyone that shoots will have a different group based upon the variation is the operator.    The variation cna be as much as you noted. 4" but that still gets a person on a torso at 50 to 75 yards.

It is my belief that two shooters will never have the exact same sight picture, aligment, form etc when shooting a gun with iron sights, therefore will likley not have the same POI. For this reason I carry a peronsally owned AR on duty per dept policy. Plus I know how the gun is taken care of etc. I however can pick up someone elses AR and shoot it and be minute of person at 100 but caulk that up to having shot thousands of rounds (I know that kinda contradict what I just said, LOL).

This is the opposite of what our Firearms training cadre (which I am not a member of)belives. They sighted in all the Dept owned AR's and then everyone else qual'd with them. With that said at 100yards most everyone had little to no problem qualifing, even people who this was the very first time that had ever held a rifle. I did not keep track of differences between shooters and guns however, but likely will note it at the next qualifing round.

In your case could it be an eye dominance issue? Maybe one of the shooters is opposite eye dominate and that is accounting for the shift? Maybe one of them would be more comfortable shooting the gun opposite handed. My Sgt is right handed but can not hit the side of a barn at 50 yards right handed with a rifle, when he shoots lefty he is dead on out to 100 no prob. He shoots pistol righty. he just finds it more comfortable to shoot the rifle left handed and we think he is opposite eye dominate.

Hope this helps
J-

wow, really fleet weapons.  I dont think I could do that.  I have had several AR's issued to me at one time, each one shot a little differently than the other.  I think issue weapons to that individual officer who trains and shoots only that weapon is very important so the officer knows what his specific rifle can do.

Well then the question is what to do with a patrol rifle that is mounted in a vehicle to be used by multiple officers?  Disqualify the officer from using it?, tell him to compensate? (liability?), have him ajust the windage if he deploys it?(libility issue?)

Would some other sighting system elliminate this problem? EOTEC, ReflexRX01 etc.

No you have to use the tools you have.  Like others have said 4 inch's at 50 is not to bad.  With training most guys should be able to handle the weapon. But they need to know the rifle and their limitations when deploying it.

Unfortunetely it's 4 inches at 25 yards and that pretty much means he's way off at 50.

Well mess around with his cross dominate eye and right and left handed shooting.  Most of the leftys at my department shot pistol with left hand and rifle with right hand even though the dominate eye was left.  Might be an issue for you to document so the department can recognize he needs to be issued his own rifle for that reason.  

We did have one guy who could not hit paper at 25 yards with AR.  He was given to mags 28 round each at 25 yards in prone.  He only had 18 on paper and not anything in what you would call a group.  Needless to say he never made it through field training but I dont know what he was going to carry if he did.

hang on....  as a small arms instructor i have to disagree on a few things  
1 EOTECH's and Aimpoints are Parallax free optics
2 for EOTECH's and AimPoints (as i install/zero/troubleshoot/instruct on these systems in particular)  the sights are zeroed to the WEAPON not to the individual shooter.  
3 Iron sights are SHOOTER defined - as in EVERYONE lines up the sights in a slightly different way, in can be from with in a millionth of an inch to as much as a tenth of an inch  differences in alignment

here are simple ways to test these
1 - EOTECH's and Aimpoints are designed to be used with both eyes open   - so place the weapon (and properly sighted sight) into a rest and look through the sight - then try closing your not shooting eye and watch as the POA (point of Aim) will NOT change
2 - I have personally demonstrated this next test on numerous ranges - take a standard rifle with iron sights (RWIS - rifle with iron sights) and have a shooter zero it then take a rifle with a properly zeroed aimpoint or eotech (RWO-rifle with optics)
 ––  next randomly select  two more shooters have one shot the RWIS, WITHOUT changing the zero and have one shoot the RWO WITHOUT changing the zero - the RWO will produce more hits over the same course of fire, on average than the RWIS  - BECAUSE the Optics are zeroed to the weapon no the shooter
3 - ask any eye doctor if human eyeballs and perceived vision are EXACTLY the same from one person to the next - not to mention vision (20/20 etc), depth perception, color blindness, etc  -  any guesses on the answer?

bottom line - if you have 1 weapon that is used for many different officers you would be better to have an optic such as the EOTECH / Aimpoint otherwise you are shooting on some persons zero not the weapons zero ––- they may be close, they may not - who's life are you willing to bet that on?

When we had wepons that were being moved between cars the fix we used was this.  There was a group of people assigned to a particular weapon.  When they took that weapon out the weapon was set to BZO and then sighted in to that particular shooter.  When they were on target they made a card and the setting were recorded on this card.  These setting were always from BZO.  The rifle was then set back to BZO and the next shooter sighted in the weapon and those adjustmens were made and recorded.  This went on for each officer.  When that weapon was issued to that officer, they would set the rifle to BZO and make their adjustments before setting out on patrol.  When they returned the weapon it was set back at BZO and the next officer set their adjustments.  After a year we took these same rifles and had the shooters put in their adjustments and they were almost always dead on.  This worked fine until we got enought to issueeveryone their own rifle.  This solution really sucks, but when you are limited on funds, it works.

Very interesting.  THis I did not know.  I assumed and I should not say that, but I zero my Aimpoint my self and make the corrections I think I need to be on target.   So this does not affect the other shooter if he grabs my weapon.    Aren't you just making the adjustments to where your eye sees the red dot.  If I site it wrong then wont it be off.  I  could never hit with one of the other instructors EoTech on his commando ,I was always off and he had his dialed down.  He could hit from 250 + on that thing.

It is not uncommon at all.

One thing I have always taught when guys got a new Aimpoint or red dot was to dial it in to the irons for a quick zero incase something happened before they got to the range to site it in.  Wont be perfect but would get ya close.

short answer is yes and no - the AIMPOINT and EOTECH were designed to be zeroed to the weapon not the shooter -  the ZERO of the weapon is a relationship between the POA and the POI - hypothetically speaking lets take a 100m "zero" (POI and POA are the exact same at 100m) - when using Iron sights we line up the sight to get the sight picture, however due to the differences in shooter/alignment/weapon there are diferences - hence we all have a different "battlesight Zero"  (this is a zero taken from a rifle that is mechanically zeroed then known windage and eleveation adjustments are added - from past experiecnces firing similar weapons -  to get the sights close to the shooters expected sight alignment - ie "close enough for government work".)
- if you zero a weapon incorrectly then you are just SOL - how the aimpoint/eotech works is that you wil have the same POA/POI for different shooters (if you are 2" high at 50m then the next guy will be 2" high at 50m)
- i understand the way you are thinking about this and let me see if i can help you with a mental picture - the sight picture you are used to seeing is compose of 2 images overlaying each other or "lining up"(front and rear sight)  the aimpoint and EOTECH's  use lenses inside the sight to put a single aligned image of a red dot onto a clear glass plate.  this red dot is aligned with in the sight (and adjustable for windage and elevation) this means that all of the "lineing up of the sights" has been done for you by the Optic.  the optic has already "aligned the sight picture" now you just have to place it on the target.
- Technical language -  "use refractive or reflective optical collimators to generate a collimated image of a luminous or reflective reticle. This collimated image is reflected off a dichroic mirror or beam splitter to allow the viewer to see the field of view and a reflection of the projected reticle (e.g. a red dot) simultaneously. If no magnification is utilized, this gives the viewer a theoretically parallax-free image of the reticle, superimposed over the field of view at infinity"
  ––  if you "zero" your aimpoint or EOTECH to 100m where the red dot is exactly on (ie POA and POI) at 100m then the next person who shoots will have the same results
- the design of the parallax free sight - ( a good picture  - http://en.wikipedia.org/wiki/Reflex_sight )

Also to help you out here are a few myths and answers about aimpoints or eotechs
- i have to put the dot on top of the front sight post - false - the iron sights are actually in the way and serve no purpose for the optics (hence the evolution of fold down sights)
- i have to aim differently when using the aimpoint/eotech - false  - you aim the same way if you normally aim 2" low at 50m with iron sights then you would do the same with the optics (your bullet flight path is not affected by the optic)
- i use the same targets to zero Aimpoints and EOTECHs and Iron sights - False - while you can utilize the same targets for general marksmenship EACH optic has a SPECIFIC target to be used when zeroing the weapon.  this is because the optics heights are differnent  - call the manufacturer and they will be happy to email you a copy of the zero targets - (hint MAKE SURE YOU ASK WHAT SIZE THE GRID SQUARES ARE SUPPOSED TO BE!!!! (ie 1cm by 1cm) or (1"by 1")- becasue when you print them out and then copy them they will be different then what the manufacturer has specified.  
- i am not a good speller - True - i have never been one

r-w-s,

Thanks for clearing that up.  So the optics just take out the variable of different alignments of different shooters.  So If my Aimpoint is sited right on and Im hitting with it where I want then the next guy should be on the same spot or vary vary close.  Well I hope that helps the original OP, never had to worry about any of that as my department issued everyone their own patrol rifle.

Variations in eye relief, stock weld, bone alignment, etc... will change the POI from shooter to shooter,  in some cases even change the POI with the same shooter in different positions.  GOOD optics remove a lot of those variables, not all, but more than enough to make them negligible.  The thing to keep in mind is rifle marksmanship is both a science and an art,  so rule #1 is if something works well for you do not try to "fix it".

I had read about your "system" in Police magizine a couple of years ago and have suggested it to other dept's (mine included) in the past as a good way to help with this problem.

J-

Yes, assuming you have accurately dialed your rifle and the shots are truley hitting where the optic "says" they should, if another shooter has a substantially different group - they are not shooting correctly.  

runs-with-scissors is spot on....  Sghts are zeroed to the rifle not the shooter, I have argued this point many times and proven my point as well.  

So what you are saying is iron sights are sighted to the shooter and optical sights are sighted to the rifle.  That can be a selling point for having optical sights for patrol rifles mounted in the vehicle and used by everyone.

On another note, I noticed yesterday that when lefty made his sight adustment he had to move the windage 16 clicks left which brought the sight markings to a point one line left of the center sight marking.  When it is at the original zero it is one line right of the center marking.  Just curious, as this rifle was sighted in by a right hand shooter which resulted in the the rear sight being moved the one line right of center, would it be fair to say a left hand shooter would need to be one line left of center to be on target?

short answer - yes - iron sights are more shooter dependent than Aimpoints or EOTECHs.   Hypothetically speaking lets say iron sights are 70% gun and 30% shooter - Aimpoints and EOTECHs would be 99.5%gun and .5% shooter  (understand that this is a vast simplification of many different variables/attributes/actions etc).  As an officer safety / use of deadly force issue the facts are that - optics zeroed to the weapons present a much more controlled application of deadly force, if an officer is forced to take a quick shot to defend a fellow officer/civilian he will be more accurate with the optic sighted weapon.
 - here is the LIABILITY question - if you know that your rifle is zeroed to a specific officer and you allow another officer to engage a target with that rifle knowing that he is not zeroed to it and that his aim will be off, what is your/the department's/the city/the authorizing supervisors liability?  
––  i don't know if there is a universal answer to this question but if your city balks at the price of the optics run this question past your city attorney.

i would not be able to make any generalizations on right handed shooters needing to click right and lefties click left - this is based on my experience in teaching the classes and range time.  sight pictures are shooter dependent - we can show the "perfect" one in class but how each person implements that is slightly different

another tool i used to "reeducate" some of the shooters on correct sight pictures - was to take weapon and put it in a shooting vise then, using the iron sights i would zero the weapon.  once i had it to where the POI and POA were exactly the same and i had a "correct" sight picture, i would have the shooter get behind the weapon and look thorough the iron sights and put a few rounds through the weapon to retrain the sight picture that he/she had to the new "correct" one.

to give you an idea of accuracy  - with a used military M4 and military issue ammo - once an Aimpoint or EOTECH is properly seroed - you can reliably and consistantly put rounds into a man sized target at 400m without a problem, this can be repeated by other randomly selected shooters using the same rifle /optic/zero.  You would be hard pressed to be able to recreate that same accuracy with iron sights using the multiple random shooters with the same rifle/sights/zero.

Basically yes, but In a perfect world all types of sights are adjusted to the rifle.

Different shooters have different sight pictures and sight alignment hence the reason Iron Sights typically need to be adjusted when a rifle changes hands.

Parallax free optics eliminate sight alignment/sight picture issues, but it does not compensate for poor form.

If your agency has Fleet Weapons I would use any argument I could to get Aimpoints or some other type of parallax free optic.

Pretty much; BUT this assumes a persons zero does not compensate for some problem with their technique.

nevermind

Sorry bro, but thats a bad idea.

Not saying its great but its better than nothing.  Technically they are not supposed to have it on rifle until they qual with it.

Cops will be cops.  

We have three AR rifles for 15 officers. I qualify them from 5 to 100 yards and no one has ever had a problem qualifying.

As others have said, no too shooters will have the same sight alignment/picture. Of course it would be ideal to have a rifle for every officer, but in most depts there is no way that is going to happen!