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Glock 20 Holsters

Custom Kydex Glock 20 Holsters

Most of what gets written about holsters assumes you are trying to make a pistol disappear. Very few Glock 20s are bought for that. This is a 10mm that goes into timber, onto a hip over a jacket, or across a chest on a pack strap — worn openly, in weather, while you are moving.

So the shell has a different job here. It has to hold thirty-seven ounces of loaded pistol still through a day of walking, and it has to still let go cleanly when your hands are cold.

Build Your Glock 20 Holster
Check Large-Frame Fitment
Grey Titan Convertible Kydex holster and magazine pouch set with bronze hardware

1.12 in

Slide width
Against an even inch on a Glock 17. That eighth is why the large-frame guns share nothing with the rest of the range.

4.61 in

Barrel
Longer than a Glock 17 and nearly a full inch and a half shorter than the long-slide Glock 40.

37 oz

Loaded weight
Glock lists it with a full magazine, and every ounce of that is asking your belt and your shell a question.

15+1

Of 10mm
The reason people carry it where they do, and the reason the recoil impulse is harder on mounted hardware.

Pick Your Variant

Gen 4 or Gen 5, and What Else Is Large-Frame

The Glock 20 comes to us in two generations, and the pistols people mistake for it are all in the same large-frame family. That family is where the confusion lives, because within it the differences are real and between it and the standard frame nothing crosses at all.

PistolWhat it isOrder this
Glock 20 Gen 4The 10mm on the large frame, textured grip and finger grooves.Glock 20 Gen 4
Glock 20 Gen 5Same envelope, grooves removed, Marksman barrel.Glock 20 Gen 5
Glock 21The .45 twin. Glock publishes it at exactly the same dimensions.Glock 21 Gen 4 or Gen 5
Glock 4010mm long slide — an inch and a half more barrel.Glock 40
Glock 29The subcompact 10mm, nearly an inch shorter in the grip.Glock 29

If you are not sure which generation you have, look at the front of the grip. Three moulded finger grooves means Gen 4; a smooth front strap with a small flare at the base of the magazine well means Gen 5. Both are separate lines in the configurator.

Cross-Fit

The Large Frame Shares Nothing With a Glock 19

This is the row of the catalogue where “a Glock is a Glock” stops being true. Everything below is measured off Glock’s own published figures rather than off feel.

FirearmShares this shell?What to order
Glock 21Ask usGlock lists both at 7.52 in of slide and 1.12 in across it. We hold them as separate lines, so tell us which you own.
Glock 40NoNine and a half inches overall against eight. The muzzle runs well past where the shell closes.
Glock 29NoSame width, an inch shorter in the grip and nearly an inch shorter in the slide. It sits far too deep.
Glock 17 or Glock 19NoThose slides measure an even inch across. A large frame will not enter the mouth of one of their shells.
Glock 20 with a threaded barrelAsk usThread protectors add length at exactly the point the front of the shell is closing on.
Glock 20 MOSAsk usFrame and slide are unchanged, so only the sight track moves. Name the optic and we cut to it.

The Glock 21 row is worth reading twice. Glock publishes the 20 and the 21 with matching barrel, slide, height and width — the calibre and the magazine capacity are the only listed differences. We still hold a line for each rather than selling one shell for both, so order the pistol you actually own and the fit is settled either way.

Carrying it in the timber?

Tell us the generation, whether it wears a light, and how you plan to wear it. Chest, hip and belt builds are all on the bench.

Start Your Glock 20 Build
Carry Style

Wearing a 10mm Where It Is Meant to Go

Almost nobody appendix-carries this pistol, and we would rather say so than sell you the wrong build. These four are how Glock 20 owners actually wear them.

Glock 20 Outside the Belt

The default, and the right one. Over a jacket, on a proper belt, where a heavy pistol can hang without pulling at you.
Shop OWB

Glock 20 Inside the Waistband

Possible, and honest about it: a large frame inside the belt is a winter and cover-garment proposition rather than a summer one.
Shop IWB

Glock 20 Sidecar

A second fifteen of 10mm is heavy. Spreading gun and spare across one platform beats hanging both off separate clips.
Shop Sidecar

Large-Frame Mag Carriers

The 10mm magazine is a wider body than a Glock 17 stick, so the pouch is pressed on its own mold.
Shop Mag Pouches
Lights & Optics

What 10mm Recoil Does to Mounted Hardware

Tan Veritas Series Kydex OWB holster shell molded for a weapon light

Worth saying on this page and no other: 10mm is hard on things bolted to the gun. Lights walk loose on their rails and optic screws back out under an impulse a 9mm never generates. A shell that lets the pistol shift makes that worse, because every draw and every step adds a little movement of its own. The full-length rail takes the serious bodies:

  • Streamlight TLR-1 HL, the usual pairing on a woods gun
  • SureFire X300U-A and X300U-B
  • Streamlight TLR-7A where you want less bulk on a belt rig
  • Olight Baldr Pro and PL-2 Valkyrie

Red dots. The MOS slides take a plate stack; plenty of large-frame guns arrive here with a slide milled instead. Either way, tell us the sight, because the channel is cut to the exact housing rather than trenched deep enough to clear anything. On this platform a snug channel is doing more than usual — it keeps the top of the shell in contact with the slide, which is what stops a heavy pistol rocking.

The build shown is a two-tone outside-the-belt shell with the mouth reinforced for repeated hard draws.

Ask About a Woods Carry Build
Recommended Builds

Three Builds for a Woods 10mm

These lean outside-the-belt for a reason. Pick the generation, the light and the mounting hardware when you configure it.

OD green Veritas Series Kydex OWB holster with quick-detach mounting

Veritas Series OWB — QLS / RTI

$75

Quick-detach outside the belt, which is what you want on a gun that moves between a range belt, a pack strap and a hunting rig.

Build the Veritas
Flat dark earth Ares Series Level 2 retention OWB Kydex holster with Tegris strap

Ares Series OWB Holster

$125

Active retention outside the belt. On a pistol this heavy, being able to move hard without watching the gun is the whole point.

Build the Ares
Black carbon fiber Kydex single magazine pouch for outside-the-waistband carry

Single Mag Pouch OWB

$30

Pressed for the wide large-frame magazine rather than a standard Glock stick. Rides outside the belt alongside the holster.

Add a Mag Pouch
Compare

Glock 20 vs 21 vs 40 vs 29

The whole large-frame family in one table, taken from Glock’s published figures. The 20 and the 21 row is the one that surprises people.

Glock 20Glock 21Glock 40Glock 29
Chambering10mm Auto.45 Auto10mm Auto10mm Auto
Barrel length4.61 in4.61 in6.02 in3.78 in
Slide length7.52 in7.52 in9.02 in6.77 in
Height with magazine5.51 in5.51 in5.47 in4.53 in
Slide width1.12 in1.12 in1.12 in1.12 in
Flush capacity15+113+115+110+1

Read the slide width row across. All four measure the same, and none of them measure what a Glock 17 or 19 does — that single number is the whole reason the large frame is a separate platform rather than a bigger version of the one you know. Within the family, length is what separates them, and the 20 sits in the middle: enough barrel to make 10mm worth loading, short enough to still wear on a belt all day.

Why Neptune

What a Heavy Pistol Asks of a Shell

A loaded Glock 20 is close to twice the weight of the micro-compacts most Kydex is designed around, and weight changes what fails. What we do differently on this pattern:

  • Retention set so it holds through movement rather than just through standing still, because a gun this heavy will find any slack you leave it.
  • A mouth reinforced to survive being drawn and reholstered with gloves on, which is when most woods carry actually happens.
  • Hardware chosen for a belt that is already carrying weight, so the mount is not the part that gives up first.

Cut and formed to order in Middle Tennessee by a veteran-owned shop, one shell at a time. More about the bench, or see every Glock pattern we press.

Blue carbon fiber Ares Series Level 2 OWB holster on Tegris belt straps
FAQ

Glock 20 Holster Questions

Dimensionally they are the same pistol. Glock publishes both the Gen 5 Glock 20 and Glock 21 at a 4.61 inch barrel, a 7.52 inch slide, 8.07 inches overall, 1.12 inches across the slide and 5.51 inches tall — calibre and magazine capacity are the only listed differences. We still hold a separate line for each rather than selling one shell as covering both, so order the pistol you own. If you happen to have both, tell us and we will talk it through rather than guessing on your behalf.
No, and not by a small margin. The large-frame Glocks measure 1.12 inches across the slide where a Glock 17 or 19 measures an even inch. That eighth of an inch is more than any shell has in tolerance, so a Glock 20 will not enter the mouth of a standard-frame holster at all. It works the other way too: a Glock 19 dropped into a large-frame shell has nothing gripping it. They are separate platforms.
Outside the belt, on a belt stiff enough for the weight, or on a chest rig if you are wearing a pack whose hip belt would otherwise cover the gun. A loaded Glock 20 runs around 37 ounces, which is roughly double a micro-compact, and that weight is what dictates the answer. If you are moving hard through brush or on steep ground, an active-retention build like the Ares is worth the extra over a passive shell.
It affects everything bolted to the gun more than a 9mm does. Weapon light mounts loosen, optic screws back out, and any movement the shell allows adds to that over time. This is one of the few pistols where we would push you toward a snug sight channel rather than a generous one, because the top of the shell staying in contact with the slide reduces how much the pistol can rock during carry. Check your optic screws regularly regardless of who made your holster.
Yes, as its own line. The Glock 40 is the long-slide 10mm at 6.02 inches of barrel and 9.49 inches overall, against 4.61 and 8.07 on the Glock 20, so it is roughly an inch and a half longer at the muzzle. That difference lands entirely at the closed end of the shell, which means the two cannot share one. Order the Glock 40 pattern if that is what you are carrying.
You can, and we build for it, but we would rather be straight with you about what it involves. It is a full-size pistol on a wide frame at 1.38 inches overall, so it needs a real cover garment and a belt that will not sag. Most owners who carry one daily do it outside the waistband under a jacket in cooler months and switch to something smaller in summer. If concealment is the priority year-round, the subcompact Glock 29 is the same calibre in a much easier package.
Yes, at the same price as right-handed, from a mirrored mold rather than a right-hand shell with the hardware relocated. Choose Left under Hand when you configure it. That applies to the active-retention Ares builds as well, which matters here because the retention mechanism has to fall under the correct thumb rather than being reachable across the gun.
Outside-the-belt builds start at $75 for the quick-detach Veritas and run to $125 for the Ares with active retention, with a large-frame magazine pouch at $30. Everything is made after the order comes in, on a ten to fourteen business day window. Tell us your generation, your light and your optic at checkout — on a pistol with this much hardware hanging off it, that is what keeps the build inside the window.

Build Your Glock 20 Holster

Generation, light, optic and how you intend to wear it. What comes back is pressed for a large-frame 10mm and holds it like one.

Configure Your Glock 20 Holster
Ask About Chest Carry

More fitment: all Glock holsters · holsters by firearm brand · Glock 17 holsters

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