An Ode To The ERGO Gapper, The Best Cheap Upgrade For The AR

Daniel Y
by Daniel Y

I love the ERGO Gapper. It’s an ingeniously simple device that makes a huge difference in AR comfort. Please allow me to share with you the best $3 you can spend on your rifle.

Reviews @ TFB:

This isn’t truly a review, but it treads close to that line so disclosures are in order. I have no relationship with ERGO. I have bought Gappers over the years, but have no connection to the company apart from being a regular retail customer.

What Is It?

The standard AR-15 trigger guard is an ingenious design with a hidden feature. One complaint about the trigger guard area is that it’s too small for use with gloves. To fix this, the mil-spec design can open by pressing the small silver tab at the front of the trigger guard. If you have a standard AR lying around that might be a feature you didn’t know about previously.

The downside of that design is the small void it leaves between the pistol grip and the trigger guard. Many shooters (including me) are very bothered by that gap. It has some sharp edges, and it sits right on top of the knuckle of the middle finger. That gets very annoying under recoil or even just carrying it around. ERGO’s Gapper fills that void.

The offending gap between the trigger guard and the pistol grip.
ERGO Gapper in the factory packaging.
It is a really simple device, with a small half-circle cut out and sides of different lengths.
The long side covers the gap, and the short side sits on the inner side.

How To Install

In order to get the Gapper in position, the grip needs to be removed or at least loosened. On the Mark-12ish rifle, it only took loosening the grip to get the Gapper in place. But on my competition service rifle with an Aero lower, I had to fully remove the grip to get it installed. Whether the grip has to be removed or just loosened, make sure not to lose the safety detent or detent spring. Also, be sure to check the safety function once the gun is reassembled.

My Mark 12ish build (set up as a spare CMP service rifle) needed a Gapper.
The Gapper does not fit with the grip in place.
Loosening the grip to get some extra space behind the trigger guard.
With the grip loose it almost fits, but it needs a little more space to fully seat.
The Gapper is fully seated! Now it is time to tighten up the grip screw to be done.
All installed!

What Difference Does It Make?

I have a worn spot on the knuckle of my dominant hand from shooting older AR-15s. That little gap has annoyed me for years. I first bought a Gapper several years ago and installed it on a retro build (a customer had his C7 upper swapped out for a flattop, and I took his C7 for $20, thus spawning another gun) with an A1-style grip from Brownells. It was immediately a huge improvement. More Gappers have found their way onto my various retro guns over the years as I remember to buy more of them.

Now, there are other ways to address this same issue. Some trigger guards (like the Magpul one) fill that space while enlarging the trigger guard pocket. The enlarged pocket leaves room for gloves, so the swing-open feature of the mil-spec guard is redundant. There are also some pistol grips (like the BCM Mod 3) that include a small shelf to cover the gap. And yet another solution comes in the form of lower receivers that have machined-in trigger guards and no gap.

But on some guns, none of those seem quite right. I cannot bear the way an enlarged trigger guard looks on an otherwise retro rifle. Putting a Gapper onto a classic AR makes it more comfortable without changing anything in a way that makes the gun look wrong.

The Aero lower needed to have the grip fully removed to get the Gapper in place. Don't lose the safety detent or spring!
Grip removed, and Gapper in place. The fit between both sides of the gap was tight but it fit once both sides were pushed down.
Fully installed!

Check Prices on ERGO Gappers


If you have a rifle with the traditional trigger guard, you should absolutely pick up the ERGO Gapper. You can keep the traditional lines of a retro gun while enjoying improved ergonomics. And possibly best of all, it is a very cheap upgrade. Try one out, and you might be surprised at the difference it makes.

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Daniel Y
Daniel Y

AKA @fromtheguncounter on Instagram. Gun nerd, reloader, attorney, and mediocre hunter. Daniel can still be found on occasion behind the counter at a local gun store. When he is not shooting, he enjoys hiking, camping, and rappelling around Utah.

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6 of 23 comments
  • Ahab Ahab on May 07, 2024

    ? Just buy a new trigger guard for 6 dollars more?

    • See 1 previous
    • Nasty! Nasty! on May 13, 2024

      @Heat is overrated I recall seeing a guy say that he bought a big bunch of them which shared with everyone else on base when serving in Afghanistan.

  • GeorgeSmythsonIII GeorgeSmythsonIII on May 07, 2024

    never saw that as an issue... so this, to me, seems to be a solution in search of a problem... (and, I have built and own several ARs, not a newbie...)

    • See 1 previous
    • GeorgeSmythsonIII GeorgeSmythsonIII on May 21, 2024

      @raz-0 I've put thousands of rounds thru mine... also, I don't skimp on quality for the lowers... I haven't experienced an issue.