Which Faxon Barrel Fits Your Glock®? A Model-by-Model Guide

Pistol Barrels • Fitment Guide

Short version: a Faxon G19 barrel fits the Glock® 19, the Glock® 45, and the Glock® 19X, because all three use a G19-length slide and barrel. The Glock® 45 is a 9mm pistol, not a .45 ACP. On the G19 one barrel covers Gen 2 through Gen 6; on the G17 and G34 the Gen 2–4 and Gen 5–6 barrels are not interchangeable, and the difference is the locking lug rather than the length. The G43/43X and the G48 share a frame but not a barrel. Below: the full model-by-model table, which G19 barrel to pick, and what to do if your pistol is not listed.

Which Faxon Barrel Fits Your Glock®

If you are holding a Glock® and wondering which of our barrels drops into it, start here. Everything on this page is a 9mm barrel unless it says otherwise.

Does a Glock® 19 Barrel Fit a Glock® 45?

Yes. If you own a G45, a Faxon G19 barrel is the barrel you want.

The reason is the way the pistol is built. The Glock® 45 is a Glock® 19-length slide and barrel on a Glock® 17-length frame — a crossover pistol. The longer grip holds 17 rounds; the shorter slide handles and carries like a 19. The barrel is the G19 half of that equation, so a G19 barrel drops straight in. The Glock® 19X is built the same way and takes the same barrel.

One thing worth clearing up

The “45” is a model number, not a caliber. Glock® reused the number the way it reused 17, 19 and 43. If you came here looking for a .45 ACP barrel, this is not the page you want: the Glock® 45 takes 9mm, and so does every barrel listed above.

This trips up enough people that it is worth saying plainly. It is the single most common reason someone searching for a “Glock® 45 barrel” ends up on the wrong product.

Which G19 Barrel?

Nine Faxon barrels fit the G19, G45 and G19X equally. Every one of them is machined, finished and headspaced in Greater Cincinnati, Ohio, and the choice between them is steel, fluting, finish, and whether you want threads.

Duty Series

4150 CMV steel, salt bath nitride, conventional rifling, drop-in fit. The straightforward upgrade, and the one for a pistol that gets carried in weather. Non-threaded ›  •  Threaded ›

Match Series

416-R stainless, tighter tolerances, and the patented Flame Fluted® profile that takes weight out of the barrel without taking it out of the bore walls.

Generations: When They Matter and When They Do Not

This is where most compatibility questions actually come from, and the answer is different depending on which Glock® you own.

On the G19, one barrel covers Gen 2 through Gen 6. Our G19 barrels carry the Gen 6 relief cut as of Job #16477, which is engraved on the non-ejection side of the barrel hood. Barrels made before that job are still Gen 6 compatible, but increased wear in the area of the relief cut is possible.

On the G17 and the G34, the generations are not interchangeable. Our spec sheets name the fit exactly: the earlier barrels read Glock® G17 (Gen 2-4), the later ones Glock® G17 (Gen 5–6), and the same split applies to the G34.

The difference is the locking lug, not the length. Both G17 barrels measure 4.49″, so you cannot tell them apart by holding them up next to each other. What changed between the generations is the lug that locks the barrel into the slide. A barrel of the wrong generation will not simply run a little differently — it will not fit correctly at all. Check which generation your pistol is before ordering, and if you are unsure, ask us rather than guessing.

The G43X and the G48 share a frame, not a barrel

There is no generation split on the slimline pistols, but the 43X and the 48 are not interchangeable with each other. They share a frame and a magazine, and the numbers on our own spec sheets say the rest: the G43/43X barrel is 3.41″ and the G48 barrel is 4.19″ non-threaded (3.92″ and 4.69″ threaded). Three quarters of an inch apart, and one of the more common mix-ups we see.

Threaded or Not?

Every model above is offered both ways. A threaded barrel lets you mount a suppressor or a compensator and ships with a thread protector. A non-threaded barrel is the drop-in replacement for a factory barrel and keeps the pistol the same overall length.

If you are not running a can today but think you might, the threaded barrel costs you nothing in function: the thread protector sits flush to the muzzle, and most open ended holsters still fit.

Model by Model

Glock® 17

Full-size 9mm, 4.49″. Duty and Match Series, threaded and non-threaded, with TiN and Chameleon PVD on the Gen 2-4 Match barrels. Mind the generation split. All G17 barrels ›

Glock® 19, Glock® 45, Glock® 19X

Our deepest Glock® line: nine barrels covering Duty and Match, four finishes, threaded and non-threaded, Gen 2 through Gen 6. One barrel family for all three pistols. All G19 barrels ›

Glock® 34

The long-slide competition gun, 5.31″. Same Duty and Match split, same generation caveat as the G17. All G34 barrels ›

Glock® 43 / 43X

Slimline single-stack and its wider-gripped sibling, 3.41″. One barrel covers both, in Duty and in Match with TiN, Chameleon and Nickel PVD options. All G43/43X barrels ›

Glock® 48

Slimline with the longer slide, 4.19″. Shares a frame with the 43X but not a barrel. Duty ›  •  Match Fluted ›

Glock® 22 — the 9mm conversion

A different animal: this converts a .40 S&W Glock® 22 (Gen 2-4) to shoot 9mm. The barrel is not the whole conversion. We encourage running 9mm magazines and a 9mm recoil assembly — guide rod and spring — alongside it. Neither is included with the barrel, so budget for all three parts before you start. G22 9mm conversion barrel ›

If Your Model Is Not on This List

Glock® has released a lot of pistols, and we do not build a barrel for every one of them. If you own a model that is not listed above, or you are not certain which generation you have, contact us before you order rather than assuming a neighboring model’s barrel will work. We would rather answer a question than process a return.

The same goes for any combination this page does not state outright. If it is not written here, we have not confirmed it.

Glock® Barrel Fitment FAQs

Does a Glock® 19 barrel fit a Glock® 45?

Yes. The Glock® 45 uses a Glock® 19-length slide and barrel on a Glock® 17-length frame, so a Faxon G19 barrel drops straight in. The same barrel also fits the Glock® 19X.

Is the Glock® 45 a .45 ACP?

No. The Glock® 45 is a 9mm pistol. The 45 is a model number, not a caliber, the same way 17, 19 and 43 are model numbers. Every Faxon Glock® barrel listed on this page is 9mm.

Does a Glock® 19 barrel fit a Glock® 19X?

Yes. The 19X is built the same way as the G45: a G19-length slide and barrel on a G17-length frame. It takes the same Faxon G19 barrel.

Will a Faxon G19 barrel work in a Gen 5 or Gen 6 Glock® 19?

Yes. Faxon G19 barrels cover Gen 2 through Gen 6. Barrels from Job #16477 onward include the Gen 6 relief cut, engraved on the non-ejection side of the barrel hood. Barrels made before that job are still Gen 6 compatible, but increased wear in the area of the relief cut is possible.

Why will a Gen 2-4 barrel not work in a Gen 5 Glock®?

The locking lug differs between the generations. The barrels are the same length — both G17 barrels are 4.49″ — so the difference is not visible at a glance, but the lug is what locks the barrel into the slide and it has to match. This applies to the G17 and the G34; the G19 is unaffected, because one Faxon G19 barrel covers Gen 2 through Gen 6.

Can I use a Glock® 43X barrel in a Glock® 48?

No. They share a frame and magazines, but the barrels are different lengths: 3.41″ for the G43/43X against 4.19″ for the G48, non-threaded. Order the barrel for the pistol, not for the frame.

Do I need a gunsmith to install a Faxon Glock® barrel?

No. These are drop-in barrels and install the same way as a factory barrel field strip. No fitting, no gunsmithing.

Shop all Glock® barrels ›

Barrel lengths and generation fitment are taken from Faxon product specifications; lengths are nominal and threaded versions run longer than their non-threaded counterparts. GLOCK® is a registered trademark of Glock Ges.m.b.H. Faxon Firearms is not affiliated with, endorsed by, or sponsored by Glock Ges.m.b.H.