Conversion barrels for Glocks 19, 22, 23. (Photo: Kristin Alberts)
Glocks may not be much to look at, but they sure are a joy to shoot. As many models of Glocks exist, there are even more aftermarket companies building toys to trick them out. And leading the way are aftermarket conversion barrel companies. Can’t decide between a Glock 23 in 40 cal or the Glock 19 in 9mm? Now you don’t have to. Buy the Glock 23 and then order a conversion barrel in 9mm. Boom. Two guns in one. But which barrels to buy?
Glocks with various conversion and factory barrels. Conversion barrels can go down in caliber but not up. (Photo: Kristin Alberts)
What’s a conversion barrel?
These barrels are exactly as they sound—barrels that convert a gun from one caliber to another. As a general rule of thumb, you can move down in caliber—or remain constant—but not up. For instance, our test barrels turned a Glock 23 .40SW into both a 9mm and a .357 Sig. There’s also a conversion from a Glock 20 10mm Auto into a 45ACP.
All of the barrels we tested were super simple, swap barrels. (Photo: Kristin Alberts)
The barrels we tested are all “plug-and-play.” You buy the new barrel and ammo and hit the range. No changing of the slide or the spring and no gunsmithing. Though it is advisable to acquire the appropriate caliber magazines for true reliability in feeding, we also used the stock Glock mags from the original gun just for comparison’s sake.
The conversion barrels allow you to make other changes as well. Want to screw-on a suppressor? Go with a threaded barrel. Displeased with the groups from your factory tube? There are longer barrels, compensated ones, or match grade.
Threaded barrels mean that conversion barrels can also be used to add suppressors to guns. (Photo: Kristin Alberts)
For this review, Guns.com looked at the four most popular Glock conversion barrels on the market: Bar-Sto, KKM, Lone Wolf, and Storm Lake. We reviewed price, build quality, available options, accuracy at 15 and 25 yards, reliability, lead times, customer service, and packaging.
Headquarted in Sturgis, South Dakota, Bar-Sto Barrels is a fine American company building semi-auto pistol barrels since 1971. Bar-Sto barrels are machined from 416 stainless steel bar stock which has been heat treated 39 to 43 RC and 180,000 PSI tensile strength. All Bar-Sto barrels are machined, bored and rifled in house. Bar-Sto barrels have been used by the U.S. Marine Corps Marksmanship Unit, and have been used to win every major pistol tournament worldwide.
Available options include extended, ported, and threaded including a thread protector. Bar-Sto barrels are sold as either Semi Fit or Match Grade. Semi Fit are your typical drop-ins, while the Match Grades require gunsmith fitting for superior accuracy. Bar-Sto barrels are broach cut rifled to accept lead bullets. The company advertises Semi Fit barrel accuracy at “1.250 or better at 25yrds with good ammo.”
BarSto 9mm in frame and old factory barrel to the side. (Photo: Kristin Alberts)
Our semi-fit Glock 23 conversion 9mm barrel, with its 1/16” twist, performed admirably on the range and was one of the favorites of testers. Shooting Sig Sauer Elite Performance 9mm 124 grain FMJ, we achieved repeatable sub-1” 5-shot groups at 15 yards and 1.195” groups at 25 yards from the bench. All three shooters were very pleased engaging targets from the standing position. Through 60+ rounds of factory ammo, we had 100% reliability in feeding and ejecting. Another 25 rounds of reloads and 25 of Winchester white box ran without a hitch.
BarSto 9mm barrel. (Photo: Kristin Alberts)
Our test barrel, extended and threaded with 1/2x28tpi, retails for $315, making it the most pricey of the lot. A similar standard-length barrel in either 40 S&W, 9mm, or .357 Sig runs $225. You really get what you pay for though, as the fit and finish on Bar-Sto barrels is outstanding. The only minor knock is that our test barrel came packed in a plastic bag rather than a hard tube like the others. Unlike the other barrels with their knurled thread protectors, Bar-Sto’s are smooth, making it look like a more natural extension of the barrel, though not quite as easy to remove.
BarSto threaded 9mm barrel makes it suppressor ready. (Photo: Kristin Alberts)
The only drawback to one of the best aftermarket barrels out there? Bar-Sto currently advertises a 10-12 week leadtime on barrel production, though there are a few options that come in and out of stock regularly on the website. Through the testing process, I was able to speak with several reps from the company, and I am convinced of both their dedication to quality and customer service. Bar-Sto has been quietly making a name for itself at the top of aftermarket barrel production.
KKM Precision Barrels
KKM 357sig barrel for Glock. (Photo: Kristin Alberts)
From their headquarters in Carson City, Nevada, KKM Precision turns out their barrels “from beginning to end” in the USA. The barrels are button rifled from 416R stainless bar stock heat treated and vacuum tempered to 45 RC. Like Bar-Sto, KKM barrels are available in stainless finish only, but come with threaded, ported, standard or compensated options. Where other companies offer the majority of barrels with the same twist rate of 1/16”, KKM offers several different twist rates in an attempt to maintain an edge with competitive shooters.
.357 Sig versus 9mm. (Photo: Kristin Alberts)
All our testers gravitated to the KKM barrel on the bench. It just has the look and feel of quality, with a clean finish inside and out, and comes packed in a re-usable hard sleeve. Also, like the Bar-Sto, company branding on the barrels is simple, tasteful lettering around the ejection port.
Our review barrel was a Glock 23 conversion to .357 Sig, extended and threaded for 9/16x24tpi. For accuracy, we shot Sig Sauer Elite Performance .357 Sig 125 grain FMJ.
KKM .357 SIg barrel on Glock 23 with suppressor. (Photo: Kristin Alberts)
Results from the bench were very similar to our groupings from the Bar-Sto 9mm, with 15 yard groups well inside 1” and 25 yard 5-shot groups averaging 1.275.” As I do not reload .357 Sig (yet, anyway), all ammo was factory. We were impressed with the .357 Sig chambering and ended up shooting 150 rounds of both Sig Sauer Elite and also Winchester white box 125 grain JHP’s.
Including a thread protector, the retail price of our test barrel is around $230. A standard length, non-threaded drop-in conversion barrel is very reasonable at $165 given the custom nature of KKM. The company is very accessible by both phone and email, and is eager to please with an obvious attention to detail.
Lone Wolf Barrels
Lone Wolf 9mm Glock barrel. (Photo: Kristin Alberts)
Lone Wolf Barrels has headquarters in Priest River, ID. While they advertise barrels designed in the USA, the website is clear that manufacture is “outsourced to manufacturing companies based in the USA.” Regardless, Lone Wolf makes some of the most reasonably priced and common conversion barrels in the industry. Barrels are available in the most options: stainless, black-oxide, blind marked, extended, standard, threaded, ported, and compensated. Lone Wolf barrels are broach rifled and made from 416 stainless forgings and advertised to handle lead, jacketed, or plated bullets.
For what it’s worth, Lone Wolf’s website notes potential failures to eject (FTEs) with certain 115-grain 9mm ammo, specifically Winchester white box. We ran a couple mags of white box, and had one early malfunction. Our testing however, used Sig Sauer Elite Perfomance 124 grain FMJ’s and we had 100% success rate over 120 rounds. The website also notes possible issues with reloads that are not full length resized. All our reloads are full length resized and ran 40 rounds flawlessly.
A standard Lone Wolf Glock conversion barrel retails for $94.95. Our test barrel, the extended and ½”x28 threaded version for the Glock 22 comes in only a few dollars higher, though thread protectors are not included standard. Though I always grant an edge to completely made-in-America products—our test Lone Wolf barrel was manufactured by Dasan Machineries in South Korea—at those prices, it’s hard to argue against having conversion barrels in all calibers.
Though our testers were torn whether the Lone Wolf raging-wolf-head logo was cartoon or cool, the company offers the option of “blind marking” where the logo is hidden from view when the barrel is installed. Lone Wolf also offers quality custom laser engraving on slides, slide plate covers, and barrels. Like Bar-Sto and KKM, the Lone Wolf customer service line was easy to reach by both phone and email. The website is easy to navigate and clearly marks which barrels are in ample stock, low stock, and backorderable.
Storm Lake Barrels
Using Sig ammo in Glocks. (Photo: Kristin Alberts)
Storm Lake Barrels is headquartered in Lenoir City, Tennessee and advertises their barrels to be made in the USA, a point all our reviewers love. However, that’s where the love fizzled out. In theory, Storm Lake barrels sound good and are fairly priced. They’re machined from 416 stainless steel bar stock and hardened to 40-42 HRC. They are broach rifled and advertised to handle jacketed or lead bullets. Options include extended length, porting and threading.
Things fell apart when we went to testing. We acquired a new extended Glock 23 9mm conversion barrel, which came nicely packaged. Of the first 25 rounds of Sig Elite Performance, we experienced more failures, stovepipes, and fliers than successes, even with the appropriate 9mm magazine. Winchester white box came out the same, as did reloads.
Loading ramp lineup on favorably reviewed barrels. (Photo: Kristin Alberts)
We thought we had a bad barrel and headed to the gun shop. In comparing barrels there and seating and test firing further, tolerances were not as tight as those from the aforementioned three companies. There were visible differences in fit and finish between the same model barrels. One local gun shop no longer stocks or recommends Storm Lake barrels due to the volume of customer complaints over the last year—though in the past, it was his go-to aftermarket barrel.
To further complicate matters, we put in multiple phone calls and emails to the company through the contact information on the website. Only one of multiple calls to Storm Lake was answered, by a rep who identified himself as being from Tapco, a sibling company of Storm Lake under the Freedom Group parent company of Remington. He said he’d “do his best” to have a Storm Lake rep call back. That was 2 months ago. None of our testers are holding their breath, and we cannot, in any good faith, currently recommend these barrels. This is especially sad, because I shot and enjoyed Storm Lake barrels years ago.
While I looked at Glock conversion barrels, Barsto, KKM and Lone Wold all make barrels for the most popular semi-auto pistols. (Photo: Kristin Alberts)
If you’re buying a conversion barrel, buy what best suits your needs whether that’s governed by price, fit & finish, features, ultimate accuracy or a combination of factors. After plenty of range time and review by multiple shooters, we can wholeheartedly recommend three solid barrel companies. The most important part of the switch? Buy more ammo in calibers you didn’t think you had and send some rounds downrange.