Glock 20 Gen 5 Review – 10mm power!

by Ryan Cleckner

June 12, 2023



The 10mm Auto cartridge has seen a bit of a resurgence lately with most of the main handgun manufacturers coming out with a new model in past couple of years:

I’ve seen these offerings coming out and have been waiting for Glock to release a Gen 5 version of their Glock 20.

Thankfully, they’ve delivered.

I purchased one for myself and took it out to the range to put it through its paces – here’s my experience with it….

Glock 20 Gen 5 Specs

  • Caliber 10mm AUTO
  • Action Safe Action
  • Capacity 10+1 or 15+1
  • Rear Sight Black Notch
  • Front Sight White Dot
  • Slide Steel
  • Frame Polymer
  • Barrel Length 4.61 in
  • Weight 29.81 oz

Glock 20 Gen 5 Background

The Glock model numbering system is a bit odd and hard to keep track of for new gun-folks. However, it’s not that hard to follow once you spend some time around them.

Glock model numbers are assigned as a design is started – the first mainstream market offering from Glock is their G17 handgun, a full size 9mm. Then, they made it a full-auto (G18), then they made it smaller with the compact G19.

Next they started on the G20, a 10mm full size pistol followed by a full-size 45 (G21), and then a full-size and compact 40 S&W (G22 and 23, respectively). For gun nerds like me, it’s important to note that it’s no the order they are released as the G22 and the G23 came to market before the G20.

It is really interesting to me that Glock jumped to designing a 10mm after the full size and compact 9mm – that says a lot for the belief they had in the cartridge at the time.

As far as generations of Glocks go, the Gen 5 is my favorite. I liked the Gen 3 the most (previously) – I hated teh Gen 4 and the Gen 2 and First Gen lacked refinements of teh Gen 3. But when the Gen 5 came out for Glock it was such a big improvement for me, that I waited to buy a 10mm until the G 20 was improved to the 5th generation.

So, why all of the excitement for 10mm lately when it has been a fairly niche round even when it first came out in 1983?

First, it sometimes takes quite a while for a niche cartridge to catch-on as a mainstream offering. I think 10mm has always been popular for backcountry hunters as a bear and mountain lion defense round and also those of us that can never have enough power in a handgun (or are just big Gunsite, Jeff Cooper, Bren Ten, or Miami Vice fans).

Second, with the massive sales we’ve had over the past few years (largely due to anti-gun efforts and instability in the world), most of us already have all the standard firearms we need. But, since we’re gun-people, we like to buy new guns and we’ve finally made it down our list to 10mm Auto pistols.

Glock 20 Gen 5 Features

Glock 20 Gen 5 Features
1 Flared Magwell

Makes reloads easier without adding too much bulk

2 Interchangeable Backstraps

Customize grip dimensions to your hand

3 Optics Ready

Glock MOS system plates included for most red dot optics

4 Front Slide Serrations

Thankful that these are now factory options from Glock

5 Glock Marksman Barrel

I personally think these are truly more accurate Glock barrels

6 Reversible Magazine Release

Easy to switch for Left-handed use

7 Undercut Trigger Guard

A popular customization on older Glocks – makes it easier to grip and shoot

Glock 20 Gen 5 Review –  Our opinion after using it

This was difficult for me to try and give an impartial review – after all, I fully admit that I’ve been asking for Glock to release this model for at least a year and was so excited when they did, I raced out and purchased one for myself.

So, although this isn’t a free sample from a manufacturer in exchange for a good review (the unfortunate “norm” for most gun review sites and channels), it is a review of a gun I purchased because I already knew I’d love it.

Let’s run through my first couple of trip to the range while putting some hands-on experience with this big boy.


Honestly, the FN 510 was the most “shootable” 10mm that I’ve tested (and I’ve personally shot all of the main 10m contenders.

However, the Glock 20 Gen 5 is a close second place for me.

Testing Glock 20 Gen 5
Author Testing Glock 20 Gen 5

Gen 3 G20s seem a bit more difficult to hold (more like trying to hold onto a heavy recoiling bar of soap) and the Gen 5’s plastic seems a bit less “slick” and the squared off shape really helps me get a hold of the gun (more on this later under “ergonomics”).

Even if you hate Glocks, I’d encourage you to check this pistol out because they’ve really made a soft shooting and enjoyable to shoot 10mm.

As far as shoot ability goes, the Springfield XD was the worst. For this Glock, I may not want to run a full multi-day pistol course with it, but if I had to, I’d be just fine.

I shot a few boxes of ammo from the holster under time and at least half were controlled pairs (the slightly more professional way to say “double tap”). Although it surely recoils more than my 9mm pistols, I actually think that this was more shootable than something like an M&P in 40 S&W.


If no other factor convinces you to get the Glock 20 Gen 5 as your choice for a 10mm pistol, this one should convince you to do it – in my opinion (and my experience with other Glocks and this one), there is no better product when it comes to reliability.

I have this 10mm as a backcountry pistol – this means it is going to be exposed to harsh weather (cold, hot, rainy, muddy, snowy, etc) and I need it to work for self defense.

Based on reliability alone, this is the backcountry 10mm for me and I’d really question the purchase of any other 10m for this purpose.

G20 Gen 5 Firing

Glocks just work and in my experience with this pistol so far, this G20 is no exception.

Also, I feel a LOT safer with this Glock as it is not “pre-cocked” like most other offerings are. If I take a spill or tumble over a log in the woods, I don’t want to worry about blowing a 1cm hole through myself or my hunting buddy.


For may hands, the Gen 5 Glocks offer superior ergonomics to previous generations.

I used to think that finger grooves from the Gen 3 models (my prior favorite) were great to have and helped me control the pistol.

However, now that I’ve fallen in love with the Gen 5 (BTW, the Gen 4 Glocks are trash IMHO), I now have a G17, G19, G45, and G20 in the Gen 5 family.

The polymer in the frame has a bit more grip to it (it is less slippery), the texturing is rough enough to work without being obnoxious, the under-cut trigger guard was a popular customization on prior Glocks for a good reason (it feels way better on your middle finger) and is a welcome factory addition.

Another upgrade for Glocks used to be front cocking serrations on the slide – having these as options from the factory is another bonus. Add all of these up along with a comfortable mag release, and you’ll understand why I give the Glock Gen 5 pistols an “A” for ergonomics.


If you’re still reading and not thinking I’m just a Glock shill, I might lose you on this point.

The Gen 5 Glocks are more accurate for me.

This might be because of the nicer trigger (it does feel nicer) or the “marksman” barrel. However, they just shoot better for me.

With this Glock 20, I was able to keep FMJ Sellier & Bellot inside 2 inches at 10 yards easily. At 25 yards, I expected 5 inches (2 inches times 2.5 is 5 inches), however, I couldn’t keep it tighter than 10 inches. This doesn’t make sense and I’m attributing it to me having poor trigger control and anticipating the recoil.

I have yet to use a red-dot on this pistol but I can’t wait to get one on to try.


As far as value goes – I think that this Glock 20 is the best value in 10mm pistols IF you’re keeping track of accuracy and reliability.

Other 10mms like the P320 X-ten have a nicer trigger (nicer to shoot/easier to be accurate) but not a trigger I’d want in a backcountry pistol.

Final Thoughts

I think that the Glock Gen 5 20 is the best 10mm pistol on the market today.

If I were using a 10mm for target shooting only, I’d consider the Sig X-ten but since I want to be able to abuse this pistol and still have it be 100% reliable for me (is that possible?) in the field in a survival situation, it’s the Glock 20 Gen 5 for me. That’s why the Glock 20 is on our best CCW guns list for the best gun for rural carry.

I think you’d be happy with it too.

Glock 20 Gen 5 Pros and Cons 

  • Reliability – Glocks are known for their unrelenting reliability
  • Safety – The Glock action is the only action I trust for safety in teh holster as it’s being abused in the backcountry
  • Optics Ready – All new pistols should be optics ready – this Gen 5 G20 is.
  • Value – Accuracy and reliability at a decent price
  • No External Safety – I consider this a benefit but to some people it is a “con”
  • Crap Sights – AS with all Glocks, it comes from the factory with junk plastic sights

Report Card


Over the first couple hundred rounds, this pistol is really enjoyable to shoot


The Glock 20 was 100 percent reliable in our tests.


The trigger and grip are better than previous generations but it lacks a bit compared to comp


We shot the gun well at 10 yards and in. The groups spread out as we moved back, but that’s partially us and partially a small pistol with a short barrel.


The sights make up for the lack of a rail here. The price just can’t be beat, especially for what you get right from the box.

Glock 20 Gen 5 Review grade

Our Grade


Reviewed by Ryan Cleckner

Reader’s Grade


Based on 13 Reviews

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Glock Twenty 10mm Starter Pack

These three items are must haves for all firearms owners.

  • Eye Protection: Keep your eyes protected and check out or favorite shooting glasses!
  • Hearing Protection: These are our suggestions for hearing protection.
  • Gun Cleaning Kit: If you are going to carry the G20 in 10mm as your backcountry solution, you need to keep it well maintained. Check out our favorite gun cleaning kits.  

Here are some deals we found on the Glock 20 Gen 5 MOS.

Upgrades and Accessories for the Glock 20 MOS Gen 5

For handguns we always recommend a good holster a lot of spare magazines.

Upgrades and Accessories for the Glock 20

Warne Chest Rig Holster
  • Excellent for Backcountry Carry
  • Elastic and Nylon Straps
  • Kydex Holster
  • Fits G20 and G21
Check Price
Glock Factory 15 round 10mm magazines
  • Glock Factory magazine
  • 15 round capacity
Check Price
Red Dot Sight

Vortex Defender CCW

Vortex Defender CCW
  • Motion activation with 14 hour auto-shutoff
  • Shield RMS Footprint
  • Fully Multi-Coated Lenses
  • 8 Daylight Bright Brightness Settings
Check Amazon Price

Best Ammo for Your Glock 20 Gen 5

We suggest both range ammo for practice and some quality self defense ammo to use when carrying your G20.

Range Rounds

Magtech 9mm Ammo

Magtech 10mm 180gr

Cost Per Round $0.38

Defensive Ammo

Federal HST 9mm Ammo

Federal Personal Defense 10mm 200gr Grain HST

Cost Per Round $1.50

Glock Pistol Models (by number)

Glock Model NumberCaliberSizeFrame
189mm (full-auto)FullSmall
2145 ACPFullLarge
2240 S&WFullSmall
2340 S&WCompactSmall
2440 S&WFull (Long Slide)Small
25380 AutoCompactSmall
2740 S&WSub-CompactSmall
28380 AutoSub-CompactSmall
3045 ACPSub-CompactLarge
31357 SigFullSmall
32357 SigCompactSmall
33357 SigSub-CompactSmall
349mmFull (Competition)Small
3540 S&WFull (Competition)Small
3645 ACPSub-CompactLarge (Slim)
3745 GAPFullSmall
3845 GAPCompactSmall
3945 GAPSub-CompactSmall
4010 mmFull (Long Slide)Large
4145 ACPFull (Competition)Large
42380 AutoSub-CompactSmall (Slim)
439mmSub-CompactSmall (Slim)
43x9mmSub-Compact/CompactSmall (Slim)
4422 lrCompactSmall
46 (not available)9mmCompact (rotary barrel)Small
479mmFull (Convertible to G45)Small
489mmCompactSmall (Slim)

How to Care for Your Glock 10mm Pistol

Check out this video from Sootch on how to maintain your Glock pistol.

Check out the links below for the manufacturer’s website and operator’s manual.


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About Ryan Cleckner

Ryan is a former special operations sniper (1/75 Ranger) and current firearms attorney, firearms industry executive, university lecturer, and bestselling author of the Long Range Shooting Handbook.

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