Review: Shooting a Glock with Trijicon RMR red dot sight

My introduction to red dot sights came in the mid-90s.  I was working at the range in the Marine Corps Air Ground Combat Center (MCAGCC) in 29 Palms, California.  My Gunny came up to me and asked me if I wanted to volunteer to work with “an Army unit” as a liaison.   No one else wanted to do it, so I did.

Smart decision.  I ended up spending nearly three months running around the desert with a Tier 1 unit.  They had red dot sights on everything: M249s, Mag 58s, M2 50 BMGs and their carbines.  This was the first I saw red dots in military use.  The sights they  were using were Aimpoint 5000s, a model manufactured between 1991 and 1999.  A few months later I ran into a British SF unit with the same optic on some of their weapons.  I needed a red dot sight!  (Note: US Special Forces used the  Occluded Eye Gunsight, an early version of today’s red dots,  during the Sun Tay Raid in Vietnam)

In the new millennium, the red dot sight have become a standard piece of equipment for rifles and carbines, and frequently encountered on shotguns and match pistols.  Typically, the pistol mounts attached directly to the frame, creating a bulky match gun that wasn’t good for much more than shooting open class competition.

In 2009, Trijicon introduced the Ruggedized Miniature Reflex Sight, or RMR.   This compact red dot sight was durable enough to be mounted directly to the slide of a pistol, allowing the use of a red dot sights on a more practical handgun that could be used for concealed carry or duty use. This is notable difference from the frame mounted red dot equipped pistols used in USPSA and ISPC competition for the years prior.

Unlike traditional hunting scopes, red dot sights typically aren’t magnified.  While they don’t offer the shooter a  magnification advantage, they do offer the advantage of having the reticle or dot and the target on the same focal place.  With traditional iron sights, the shooter has to account for the target, front and rear sights in his sight picture.  Since the human eye can only focus at one length, the shooter needs to focus on the front sight, with the rear and target being blurry.  Focus on the target, your accuracy degrades, and at any kind of range, you’ll miss.  Red dots solve this problem, simply align the dot on the target and squeeze the trigger.

I couldn’t wait to head to the range with my customized Glock 22.  In Machining a Glock slide for a Trijicon RMR cut, I made an RMR sight cut and installed suppressor sights.  The pistol was outfitted a Trijicon RMR model RM06 with a 3.25 MOA dot I ordered from Brownells.  In Machining front cocking serrations on a Glock slide, I cut cocking serrations on the front of the slide.  I also took the time to texture the frame with a soldering iron and install a Ghost 3.5 pound connecter to lighten the trigger. The gun looks and feels great.


IMG_6269Prior to heading to the range I bore sighted the optic with a laser bore sighter.  All shooting was done with 180 grain PMC Bronze FMJ ammunition.

Holster fit wasn’t a problem, the Desantis Kydex paddle I had for my other Glock 22 needed a slight modification at its top to clear the RMR.


Conducting dry practice with a series of different targets I was able to get the dot on target faster than I had anticipated.  Over the years I’ve shot a few pistols with red dots, however, I’ve always taken an inordinately long time to find the dot.  While this dot was slower than the iron sights, it wasn’t as bad as I had remembered.


First order of business at the range was to zero the RMR.  I put up a Combat Shooting and Tactics (CSAT) target at 7 yards and fired a 4 shot group at one of the 1″ black squares. I was a little low and left.  After two more groups I felt I was ready to push the target back to 25 yards to refine the zero.

glock 22 rmr at 7 yards first three groups

First group (above, left), second group (above, middle) and the last groups at seven yards (top, right) before the target was pushed out to 25 yards.

glock 22 rmr zero target

It turns out my initial zero at 25 yards was a little high at 25 yards.  The groups around the head were the first two I fired.  I adjusted the zero and fired the last three using alternate aiming points on the target.  At this point the optic was zeroed.

I posted a new, clean CSAT target and began firing some CSAT standards.  CSAT pistol standards were developed by Retired Master Sergeant Paul Howe.  The standards are shot using sights (no point shooting) and each shot must hit the scoring area (A zone) of the target in the par time to pass.  Miss the A zone, or run over time and you fail the standard.  I shoot CSAT standards often and find them a valuable standard for comparison. For this test, I shot the following standards, par times are in parentheses:

  • One shot from the ready (1.0 seconds)
  • One shot from the holster (1.7 seconds)
  • Two shots from the ready (1.5 seconds)
  • Mozambique (2/1) from the ready (1.75 seconds)

For a complete list of CSAT standards, visit Howe’s website here.


The results of firing the CSAT standards are shown on the table above. All of the rounds hit the scoring zone, however, the times were far longer than when I shoot them with a Glock 22 with iron sights.  The red boxes above represent stages where I did not pass the standard due to time, green boxes indicate I passed.  You’ll notice more red than green.  Part of this may be because I am unfamiliar with the optic, I’d often find myself wasting time repositioning the pistol on presentation to get on target.  For comparison purposes, I’ll often shoot the 1 shot from ready with an average time of .7-.8 seconds, two shots 1.1-1.2, and the one shot from a retention holster around 1.6.  These times were considerably longer.

Next I shot the USMC Combat Pistol Program (CPP) qualification course.  This forty round course of fire uses a special target, the MPMS-1, which is a silhouette with scoring rings.  The par times are more generous than those associated with the CSAT standards.  All stages at the 7 and 15 yard lines start with the gun holstered, the 25 yard line starts from the ready position.  More information about the CPP, including the course of fire and background about its adaptation can be found here.

Glock 22 rmr USMC CPP target 388

I scored a 388, expert.  Perfect score is 400, you can see I dropped 6 shots on the right into the 8 ring of the target.  I dropped five of these at 15 yards, and one at 25.  I cleaned the seven yard line.

CPP complete, I shot the new FBI pistol qualification.  The new FBI pistol course requires 60 rounds and has stages from 3 to 25 yards and starts with the pistol holstered.   The new FBI pistol qualification can be found here.

new fbi qual glock 22 rmr 100 percent 41 x

I cleaned the new FBI pistol qual with a 60/60 (100%) and 41 shots in the center X box of the QIT-99 reverse target. During this course of fire I found myself running out of time at the close-in stages.  While I could have point shot the 3, 5 and 7 yard lines, I always use the sights on a pistol, so I took the time to find the dot in the RMR.

Next up, I shot the old FBI pistol qualification.  The older course of fire has stages from 25 yards into 5 yards.  It is a 50 round course of fire, shot hit and miss.   A complete description of the old FBI pistol qualification can be found here.

old FBI target glock 22 rmr 90 percent

Things didn’t go so well here.  I ended up shooting a 90%, which is OK, but I normally shoot 98-100% with a Glock 19 or 23.  The five rounds were dropped at the 25 yard line where I started experiencing malfunctions with the pistol not returning to battery. My initial 6 rounds from prone at 25 yards made a nice little 2.5″ group, but after that the gun started having problems.  Initially I thought it may have been shooter induced, but determined the recoil spring had failed.

Since this pistol was an abused police department trade in pistol, I suspect the additional weight of the RMR was the final nail in the coffin for the recoil spring.  By the time I finished the qualification, the pistol was basically a single shot and failed to return to battery after every round.

file glock 22 rmr

Prior to leaving the range I shot at some small targets at 50 yards.  This was a pleasure.  The single focal plane of the RMR made shooting at small targets easy.

A note on reliability of the optic equipped pistol, until the spring broke, the pistol functioned with 100% reliability.  Once it went, it went in a bad way.  I replaced the spring and headed back for a second trip to the range.

On my second trip I started by confirming my zero, which has held, and transitioned into the same CSAT standards I shot above.  My times on the second trip were eerily similar- too slow.


I shot the Marine Corps CPP and scored a 382, expert.  I dropped those two rounds on the upper right into the 6 ring and that cost me 8 points.

New recoil spring in place, the gun functioned 100% reliability on the second trip.

With 450 rounds downrange, I concluded my initial review of an RMR equipped Glock.

So what do I think of a red dot sight on a duty pistol?

  1. It is slower than iron sights.  I shot the pistol strong, weak and two handed, from the standing, kneeling and prone positions for 450 quality rounds  (we give each shot the time and attention it deserves at  I noticed about a 20% increase in time to engage targets, especially at closer ranges.  As distance increased, the difference in time to engage targets didn’t seem as pronounced when compared to a pistol with iron sights. Some of this is likely my lack of familiarity with the unit, however, I don’t predict there would be much of a time advantage over irons with increased familiarity.
  2. You are adding technology to a gun that uses a battery and can fail.  While the durability of these optics is impressive, it is still something else that can go wrong.  While the optic worked well in the 90F day, I would be concerned to see on exposed to the elements in a duty holster.  What would happened if the back of the sight filled with snow?
  3. It is a lot of fun.  It also looks cool.  As much as the RMR slowed me down, I thought it was a blast to shoot.  Definitely an interesting change of pace.
  4. The RMR didn’t improve accuracy.  We say it time and time again at, sights and triggers.  Without a proper sight picture and trigger control, you won’t shoot well.  The RMR addresses some of the sight picture, however, it doesn’t help trigger control and shot anticipation, both of which factor heavily in pistol shooting.
  5. Red dots on race guns are mounted on the frame.  This is an important distinction.  With the optic mounted on the frame, it does not move with the slide as the weapon is fired.
  6. About 3 years ago when I first owned an RMR, I mounted one on a Glock with an adapter plate in the rear sight dovetail.  This was awkward at best and the gun never even made it to the range to be test fired.  Cutting the slide is a vast improvement, lowering the height of the optic over the bore.
  7. Recessing the optic into the slide is a strong option.  A friend of mine, who is an engineer, ran a few calculations and determined it was an exceedingly strong mounting system.  He felt, given the weigh of the pistol, you’d have a hard time throwing it hard enough to sheer the screws that secure the RMR to the slide.  He also pointed out that the iron sights on a pistol aren’t held on as well as the RMR.

To learn more about how I customized this Glock pistol, please see Machining a Glock slide for a Trijicon RMR cut and Machining front cocking serrations on a Glock slide

Please help support the site!  Buy a Glock slide already cut for an RMR, click here.  To order an RMR, click here.