Modern Sporting Rifle Zeros, Or Lack Of…

By John Farnam

Red Dot vs Iron Sights
Red Dot vs Iron Sights, red dot and the back-up iron sights did not agree. this same error is common on modern MSR weapons.
Defense Training International, Inc
Defense Training International, Inc

Ft Collins, CO –-( From a friend with a big department:

“Not long ago, I supervised a standoff situation where our officers were placed in positions to engage a dangerous suspect. Several officers were armed with M4s. Bystanders were thickly mixed-in! Range to suspect was between 10 and 30m.

Happily, our situation was resolved without our officers having to shoot.

As a precaution, I asked all officers to report, with their red-dot-equipped M4s, to the range the following week. I set-up a situation with parer targets that exactly duplicated the situation with which were confronted a week earlier.

Given generous time, stable, braced firing positions, and stationary targets, not one of our officers was able to deliver required shots, even after several attempts!

When asked about sight settings and zeros, most officers were not prepared to answer definitively. Some didn’t even understand the question!

An examination of the M4s present revealed that, in most cases, the red dot and the back-up iron sights did not agree. Some were not even close!

Through rigorous training with much range time, we are aggressively addressing these issues.

Non-zeroed rifles in police service are a disaster, waiting to happen. I’ m thankful disaster didn’t happen to us,

… through no fault of our own!”


The foregoing gaffes are all too common!

Police departments have rushed military rifles into service, often without necessary accouterments, nor necessary training. Some officers understand how to set-up and run these weapons, but many don’t.

Rifles can’t be “shared.” Sight settings are individual, and each officer must have absolute confidence in his, confirmed regularly on the range. Otherwise, the rifle is little more than a big and bulky pistol, with scant chance of ever positively contributing to any tactical situation.


About John Farnam & Defense Training International, Inc
As a defensive weapons and tactics instructor John Farnam will urge you, based on your own beliefs, to make up your mind in advance as to what you would do when faced with an imminent and unlawful lethal threat. You should, of course, also decide what preparations you should make in advance, if any. Defense Training International wants to make sure that their students fully understand the physical, legal, psychological, and societal consequences of their actions or inactions.

It is our duty to make you aware of certain unpleasant physical realities intrinsic to the Planet Earth. Mr Farnam is happy to be your counselor and advisor. Visit:

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Is that not the job of the police armorer? I know officers do, or should, have range time with their carbines but I doubt they have time to go zero them in. In the military, we would pick up our M4s and the armorer already had the iron sights zeroed and the red dots sighted and co-wittnesed.

Jason Oglesby

Better than nothing, but not everyone sees the same. Almost everyone should zero their own rifle.

ole Shoemaker

WOW !!! This is just so wrong and confusing in many, many ways. This is basic knowledge and training. Who is setting the standards??? The Government, Fed and State, has standards for the average person to take a crap, let’s not even go there on business regulations, but not overall training standards and yearly qualifications for LEO ???? One would think that would be a nation wide standard. Not only that, all I hear is how much better trained a LEO is to carry a gun than a concealed carry person. I know, like any other situation, that some LEO… Read more »

William M Butler MSG USA ret

I find it humorous that the article is titled: “Modern Sporting Rifles …” and the firearm pictured is a pistol. The author had a brain fart, no doubt.

Spencer J. "Pick" Lyman

After a Near Public Shooting Catastrophe I Recall an Article Years Ago About a Police Chief Immediately After the incident Conducting a Training Exercise Where He Required His Men to Run a Course and Then Stop and Fire at a Target both Stationary and Moving, to Which, None Hit Their Mark!!!
It that Case the Officers Were the Potential Killers, Not the Criminals!

Dave Porter

It seems fairly obvious that nobody should be allowed to carry something until they can pass a fairly rigorous qualification course with it. But we live in an age where common sense is becoming more and more uncommon. Police, because they operate in areas full of innocent bystanders, need a much tougher qualification course than the military. The Army’s Combat Pistol Qualification Course uses 40 rounds to engage 30 full size popup targets at distances of 7 to 35 yards. Only 16 hits are needed to qualify to the minimum standard. Think about that for a minute. The Army says… Read more »

Dave Porter

Why do people who ought to know better still think that irons and optics need to ‘co-witness?’ The irons are zeroed at a given distance for use as iron sights. The optic is zeroed at a given distance to use the optic. Even if they are zeroed at the same distance, if you are shooting with the optic, IGNORE the irons. The aiming point of the optic is NOT a rear sight that you line up with the front iron sight, it is a standalone aiming point. You are defeating the purpose of the optic if you are just using… Read more »

Dr Dave

Master Sargent you are SPOT ON!!!!!! The optic is a straight line device designed to point straight while a bullet travels in an arc and the BUIS is a totally different process as you stated. To bad most shooters don’t get it even profession LEOS seem to be clueless as to the difference. I own a EOTech (I know don’t go there) sight that I love. I bought the outer red laser cover to add the laser capability for nights and when I just wanted to use it. It came with a separate back up set of hard sights and… Read more »

Dave Porter

Thanks Dr Dave, though I’m afraid I may be misunderstanding you. Are you saying that irons compensate for trajectory and optics don’t? If so, we will just have to agree to disagree. Since this article is about MSRs, let’s take an AR15/M-16 as an example. 20″ bbl, 62 grain bullet in the neighborhood of 3000fps. Different bbl lengths and bullet weights will be slightly different, but the same principles will apply. A zero at 36 yards -with either irons or optics- will also be zeroed at 300 yards. Zeroed meaning that bullet trajectory and line of sight will coincide at… Read more »


Thanks for the info sir!
I don’t know much about rifles except for the occasional squirrel hunt.


Part of the issue is the term “co-witness”. Too many believe that the term means that the dot has to sit above the front sight like it were if you were shooting iron sights at a bullseye.

Co-witness merely means how much of the iron sights actually appear in your optic.
Hence the “Absolute” co-witness or “1/3 co-witness”.. etc.


It’s hard to imagine with the police having to operate in such a litigious society that they would not be concerned about the the aiming points of their duty rifles. If the rifles had been employed it sounds like there probably would have been collateral damage. If you’re going to carry a rifle make sure to check it periodically to make sure it’s accurate, lesson learned.

Dr Dave

Many of you miss the obvious. 99% of LEO’s will never be in this situation so they become complacent in their equipment use training and maintenance. If the guys in question were in an area where they routinely used their long weapons they would have them cleaned sighted and ready but most never have a need to even open the trunk to make sure they have one let alone what condition it is in. Another issue is that since MOST departments do not use them often they position one or two per car but not issue one per officer so… Read more »


The picture at the head of this article does in fact look like the red dot is indeed co-witnessing the iron sights. It is the iron sights that are out of alignment.

It appears the red dot would be sitting right on top of the post if the post was in the middle of the rear sight and the top of the post and rear sight were at the same level.

L.L. Smith

Are these the people I am supposed to call if my life is in danger?

Doug Sharp

If you’re asking me. Then the answer is no. 911 is what you call after you have dealt with the problem and there is no threat. Chances are if your life is in danger or your loved ones you should be the guy holding the zeroed gun. At least until the authorities show up.


This article points to another scenario that can be just as bad in a real situation. Rifle manipulation. Given that this particular department’s officers did not comprehend how to zero their rifles, I would also bet many of them never practice how to clear stoppages or get the rifle back in the fight upon failure. Lack of familiarity will keep you on the X far too long. Yes, it would have been bad to have an incident where shots missed their intended target. It would also be just as bad to lose an officer or two because they stood confused… Read more »


Since police persons are issued handguns for their own protection and because they regularly go places most sane people try to avoid, you would think the police person would take an interest in learning how to proficiently work whatever they are carrying on and off the job. If you are in need and lucky, you will not be assisted by a uniformed buffoon who could get you killed.

2nd Amender

Anyone in the military, law enforcement, or the few unnamed agencies tasked with engaging criminals with guns, enemy combatants, and terrorist killers, will never realize until threatened personally. That experience usually sets the individuals’ resolve into a different plane of self awareness in regard to “preparedness for the worst”.

The FNG is the liability.

Mike McAllister

I always laser sight my iron and red dot/scope on every gun. It not much good if you can’t hit the broad side of a barn. You would think the police would do the same to ensure spot on sighting. Maybe this will teach a much need lesson to all and sighting in your weapon will become a common practice.

E-mail address is still [email protected] and it would be nice if your IT staff fix your site to except it. Thanks!!!!!!!!!

John M. Buol Jr.

>> Given generous time, stable, braced firing positions, and stationary targets, not one of our officers was able to deliver required shots, even after several attempts! When asked about sight settings and zeros, most officers were not prepared to answer definitively. Some didn’t even understand the question! This episode echoes many similar episodes I’ve experienced in the military as well. It isn’t unusual to find personnel in an instructor capacity (drill sergeants, etc.) just as confused. You know a demographic in the gun world that intimately understands this and doesn’t have this problem? High Power competitors. Smallbore competitors. Pretty much… Read more »

Dave Porter

Right on John. The Army doesn’t want SARG, maybe we can train the cops?

John M. Buol Jr.

Well, I’m game. I’ve taught classes at a law enforcement academy in Texas so I even have appropriate credentials to do so.

Dave Porter

Well, I’m retired now, and deep into my civilian career that the Army kept interrupting.
I do RO part time at a local shop with an indoor range, (seen some WILD stuff there) and have also done a little bit of work with the Appleseed folks. (seen mostly very good stuff from them)
I keep up on Facebook with a few of my SARG Det 34 guys. We definetly did some good work there at the McCoy RTC.
Nice chatting with you again. I think I will have to order your book.

Terrell Courson

One thing that really upsets me is the individual Officer who doesn’t even consider their duty weapon (pistol or rifle) an ancillary extension of the needed equipment for the performance of their duties during the most dire of circumstances! It’s treated more like a talisman, they are rarely seen on their own at the range (necessarily honing their skill) or much less, taking the time to wipe down the weapon to assure it’s functionality. This is the absolute last person I want watching my six!


“When asked about sight settings and zeros, most officers were not prepared to answer definitively. Some didn’t even understand the question!”

Har’s ‘yr gun!

And these are the only folks that are responsible enough to carry those evil black rifles? Mike? Shannon?

Anyone else remember the LEO that had his Eotech on backwards?

Eotech on backwards

Doug Sharp

I wonder how he didn’t notice that he had to point the rifle at himself to turn on the optic. I think they may want to have their armorer take a course or two then get their folks to the range to learn how to work with the rifles. I like 50 yard zero for tactical myself. I know close up it will shoot low and it will be a little high at 100-125 yards but generally inside 225 yards its within a few inches of where it’s aimed.