Glock page last updated: 02/17/07



Model Description Status Rating
G20 4.6" barrel and 15 round magazine capacity. Currently in 3rd generation form and available with standard black or OD green frame. In Production
G20C 4.6" barrel and 15 round magazine capacity. In Glock terminology the "C" version designates that the gun is compensated with porting in both the barrel and slide. In Production
G29 3.78" barrel and 10 round magazine capacity. Listed as a "subcompact," the G29 is more comparable in size to the midsize G19/23 pistols. In Production
Additional Notes: Glock is one of the few major firearm manufacturers who have continued to produce 10mm guns. If you're looking for the best combat gun available (where concealment is not a concern) it would be difficult to beat the Glock G20 with it's ultrareliability and 15-round firepower.

A G29, with Pearce mag extension and night sights, and its big brother the G20.


When it comes to the story of the 10mm Auto, Glock plays a very important part. While most original 10mm models (such as the Colt Delta, Star Megastar 10, S&W 10xx series, etc.) have been dropped from production, the Glock 20/29 continues. Compared to most other Glock models the G20/29 undoubtedly posts much smaller sales numbers, but the fact that it is still in production is a tribute to Glock's loyalty to the caliber.

One of the most interesting, and significant, aspects of the Glock 20 is that unlike most other 10mm firearms it was designed from the ground up to handle the 10mm Auto and not a rechambering of an existing .45 caliber design. (This is why in the Glock model numbering system the 10mm version is the G20 and the .45 ACP version is the G21.) What this means in pratical terms is that the Glock G20 has been specifically designed to handle the power of the 10mm cartridge making for a stronger, and more durable, 10mm Auto firearm.



When it comes to the Glock there isn't a lot of difference between models other than size and caliber. The G20/29 uses the largest of the Glock frame sizes, which it shares with the .45 caliber G21/30. Glock pistols are striker fired whereby the firing pin is partially "cocked" by the cycling of the slide. This allows for a DAO-style trigger pull without the long, heavy pull of most traditional DAO pistols.

G20 - The first Glock 10mm introduced was the full-sized Glock 20. This is a good-sized gun sporting a 4.6" barrel and a 15-round magazine capacity. This 15-round capacity can even be increased to 17-rounds of 10mm ammo with the installation of a +2 round mag extension!

G20C - The "C" in the G20 C stands for "compensated," meaning that this particular full-sized Glock incorporates two ports in the barrel and slide near the front sight. The purpose of these ports is to vent gasses upward to help minimize barrel flip. With a high intensity cartridge like the 10mm Auto this gives the shooter better control and allows for faster follow-up shots. On the down side, the general complaint about ported handguns is that the normal blast and flame that is usually projected forward is now directed upward, right in front of the shooter's line of sight. This can be especially disconcerting when firing in subdued light as the fireball can not only be distracting, but can also have an adverse effect on your night vision. There is also a competition version of the G20 C that can be had with adjustable sights, 3.5lb trigger and extended controls.

G29 - The G29 is listed on the Glock website as a subcompact (like the G26 9mm and the G27 .40 S&W), but it is actually more comparable to the G19 and G23 midsize pistols. The 29 is basically a chopped G20, losing both length off the slide and hight from the grip frame. The only other noticable difference is that the muzzle end of the slide has been slightly rounded to facilitate reholstering. Even with the abreviated grip, the G29 boasts a ten round magazine capacity. The standard flat magazine floorplate gives the shooter little to hang on to (not a good thing when shooting "spicy" 10mm ammo), and so a popular add-on is a "pinky extension" such as those made by Pearce Grips. This allows for a full grip and much better control.


One of the most common complaints about the G20/29 is the relatively large size of the grip frame. Compared to the 1911 Government model, or even doublestack 9mms like the Sig and Beretta, the Glock G20 and G29 are rather "blocky." Personally though, I think this is rather subjective. Unless you have unusually small hands the G20/29 is not a difficult pistol to handle. In fact, even with my medium sized hands I use a Hogue slip-on grip with my 1st generation G20. Even with the added girth of the slip-on grip I feel the fingergrooves and palmswells make for a more secure and consistent grip. For those who just can't live with the standard Glock grip though, there are alternatives. A number of gunsmiths offer "grip reduction" for polymer framed guns like the Glock. Personally I feel the results of such work are extremely ugly, but to each his own!

Shooting Characteristics

Personally, I feel the Glock 20 is one of the easiest 10mm firearms to shoot. You would think that the light weight of the polymer frame would make the G20 kick like a mule, but it doesn't. In fact it's the polymer frame that makes the G20 so a soft shooter. When shooting a metal framed gun there is zero "give" to the frame and so all the recoil is transmitted directly to the shooter. The Glock's polymer frame, on the other hand, flexes and absorbs a lot of the energy.

Fifteen rounds of 10mm ammo makes for a bit of weight. This is especially true when this weight is compared to the overall weight of the polymer framed Glock. If you take a G20 with an empty mag and then compare it with a fully loaded G20 you can really tell the difference! Common sense would seem to indicate that you would notice this change in weight as you fired the gun. It would also seem that this shift in weight would affect one's accuracy. In my experience, however, you simply don't notice and there is no perceptible change in practical accuracy.

When it comes to shooting the smaller G29 you do need to "hang on." Recoil is not unpleasant, but it is very, very snappy and there's a lot of muzzle flip. You can certainly shoot a G29 without the magazine extension, such as the Pearce unit, but it does make it very difficult to keep a consistent grip on the gun. Though the G29's size and mag capacity make it a very attractive option for concealed carry, lots of practice is a must with this gun!


November 1990 Shooting Times

Layne Simpson's article covers a number of different Glock models, including the 10mm Auto G20. Though the article doesn't focus on the Glock 20 it is still worth reading because it compares the different models which is rather interesting.

2002 Glock Autopistols

Glock Autopistols is Glock's own annual publication so it can't be considered an objective review, but the two short articles on the G20 and G29 are still interesting. Author of the G20 article, Mike Boyle, states that, "If I were limited to a single Glock pistol, the hard-hitting Glock 20 would certainly get the call." Walt Rauch writes the piece on the G29 and says, "The 10mm Auto (G29) remains, for me, the best compromise of power and controllability, balanced with the size and weight of the gun and the recoil of the cartridge."


G20/29 Grip Reduction

As mentioned above, the one major complaint about the Glock G20/29 is that the grip is simply too large. I have already stated that I believe this is more about "feel" than "size," but if you can do something that makes a gun more user friendly then go for it.

A number of custom gunsmiths perform what has been termed "grip reduction" on polymer framed pistols. On the Glock this is done by filling in the void behind the magwell that makes up the backstrap. The backstrap can then be reformed to whatever shape the customer desires, as long as it doesn't cut into the actual magwell. To finish the job the new "grip" is then retextured.

Personally, all the Glocks that I have seen with this work look really ugly, but I suppose and ugly usable gun is better than a pretty unusable gun. If you are interested in this type of customization two gunsmiths that provide this work include Robar and ARS (Arizona Response Systems).

Robar Grip Reduction

ARS (Arizona Response Systems) Grip Reduction

Glock G29 with grip reduction performed by Robar.

Glock G20L (Longslide)

Probably the most intriguing modifications for the Glock 10mm is the creation of a "longslide." L-configuration Glocks are available from the factory in a number of calibers, but not the 10mm Auto. 10mm Glock fans are not to be denied, however, and so a number of individuals have created their own G20 longslides.

The first G20L I'm aware of was put together by ColoradoGlocker of Glock Talk. As there are no true 10mm caliber longslides available, he took an aftermarket G21 (.45 ACP) longslide and mated it with a custom KKM 6" 10mm barrel that was designed to fit the G21 hood. The parts are not cheap and more than double the price of the standard G20, but it does give you a very unique gun! For more details on the steps, parts, and prices do a search for "longslide" in "The Ten Ring" forum on Glock Talk.

G20L longslide on OD frame, courtesy of nickE10mm (Glock Talk).

Scherer 29-Round 10mm Mags

Scherer is a manufacturer of aftermarket magazines and has made numerous versions for the various Glock pistols. Much to the delight of Glock 10mm fans a 29-round magazine was recently introduced for the G20/29. This new mag would be especially useful to Mech Tech CCU owners who wanted a true high capacity magazine for their carbines. Unfortunately though, these magazines proved unreliable. It was hoped that Scherer would rectify the feeding problems, but apparently these magazines have been dropped from production altogether.

Glock 20 MechTech Carbine Conversion

Mech Tech Systems, Inc. makes their CCU (carbine conversion unit) for the Colt 1911 (and clones), Beretta 92 and Glock pistols. The kit, which does not require an FFL to purchase, consists of a complete new barreled uppper receiver and stock. Basically all you have to do is remove the slide/barrel assembly of your Glock pistol and attach the pistol frame to the Mech Tech CCU upper. You then just use your standard Glock magazines.

I do not own one of these units myself, so I can only report on what I've heard from others. Though the concept is a good one, it appears that results with the G20 10mm version is rather mixed. Out of the box these carbine kits seem to be rather finiky and take a bit of "adjustment" before they run reliably. If you are looking for a cheap 10mm carbine and don't mind experimenting a bit the MechTech CCU may be the ticket. If not, the Olympic Arms 10mm AR, or the Vector MP5-10 clone might be better choices.

For more detailed information please check out the MechTech section of this website.

Mech Tech Systems, Inc.


2003 Complete Book Of Autopistols

The Mech-Tech CCU for the Glock 20 gets a "thumbs up" from author Mike Boyle. Mr. Boyle briefly goes over the background of the Mech-Tech carbine conversion unit and then gives it a good workout. This article is a good read for those considering purchasing one of the Mech-Tech CCUs.