glock 27 can use 9mm and .357 sig barrels?
- Thread starter cajun47
- Start date
Theohazard
New member
The barrels for the .357 SIG and the .40 S&W are interchangeable, but the 9mm is not interchangeable with the .357 SIG or .40 S&W; you cannot put a G26 barrel in a G27, or vice-versa.
However, you can get aftermarket 9mm barrels for your .357 SIG/.40, but keep in mind they won't be quite as optimal running 9mm. Everything besides the barrel is the same on a .40 S&W and a .357 SIG, but on a 9mm the slide, ejector, and magazine is also different.
So when you buy an aftermarket 9mm barrel to fit into your G27, the extractor has to move farther inward to grasp the case rim and the ejector is not hitting the case in the optimal way. You also need to use 9mm mags (yes the 33 round mag would work). They still tend to be fairly reliable, but I wouldn't use a gun converted in this way for self-defense.
However, you can get aftermarket 9mm barrels for your .357 SIG/.40, but keep in mind they won't be quite as optimal running 9mm. Everything besides the barrel is the same on a .40 S&W and a .357 SIG, but on a 9mm the slide, ejector, and magazine is also different.
So when you buy an aftermarket 9mm barrel to fit into your G27, the extractor has to move farther inward to grasp the case rim and the ejector is not hitting the case in the optimal way. You also need to use 9mm mags (yes the 33 round mag would work). They still tend to be fairly reliable, but I wouldn't use a gun converted in this way for self-defense.
http://www.lonewolfdist.com/
They're probably the most popular company that makes aftermarket barrels for Glocks. It's very popular for people to buy a G22/23/27, carry .40, and use the less expensive 9mm for practice/training. If I carried .40, I'd probably do that too.
They're probably the most popular company that makes aftermarket barrels for Glocks. It's very popular for people to buy a G22/23/27, carry .40, and use the less expensive 9mm for practice/training. If I carried .40, I'd probably do that too.
Hammerhead
New member
KKM makes very high quality conversion barrels for Glocks. Worth the money.
Shot this with a Glock 29 with a KKM 10mm to .40s&w conversion barrel at 25 yards off hand. Maybe not a match winning group, but I know the barrel wasn't holding me back.
Shot this with a Glock 29 with a KKM 10mm to .40s&w conversion barrel at 25 yards off hand. Maybe not a match winning group, but I know the barrel wasn't holding me back.
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Hammerhead
New member
There are some loads that are up there in the magnum revolver class, but not really up to full .44 mag class.
Maybe check out BBTI to compare calibers.
One thing I like about 10mm is that it uses heavy, long for caliber bullets that should penetrate deeper than calibers like .45acp.
Having the .40 conversion was sweet. .40 brass and ammo is far easier to find than 10mm brass or ammo.
My gun was stock except for the barrel and it ran 100% with .40 ammo.
Don't tell anyone, but in an emergency you can fire .40 ammo out of a stock Glock 10mm. The extractor holds the rounds in place for firing. I've done it with a few rounds in each of my 3 Glock 10mm over the years just to see if it would work, it did.
Maybe check out BBTI to compare calibers.
One thing I like about 10mm is that it uses heavy, long for caliber bullets that should penetrate deeper than calibers like .45acp.
Having the .40 conversion was sweet. .40 brass and ammo is far easier to find than 10mm brass or ammo.
My gun was stock except for the barrel and it ran 100% with .40 ammo.
Don't tell anyone, but in an emergency you can fire .40 ammo out of a stock Glock 10mm. The extractor holds the rounds in place for firing. I've done it with a few rounds in each of my 3 Glock 10mm over the years just to see if it would work, it did.
Hammerhead
New member
It seems like .45acp to .45 GAP would be an easy conversion, but probably not enough demand.
johnwilliamson062
Moderator
I use the Lone wolf G27 to 9mm conversion for carry. I use 9mm mags, but the 40s work without any issues also.
Theohazard hit on this, but I want it to be crystal clear...
You can not put a standard factory Glock 26 barrel in a G27.
The hole (bushing) in the front of the G27 slide is bigger than the hole in the G26 slide, a G26 barrel in a G27 will slop around.
The aftermarket barrels that convert a G27 to 9mm have the correct outside diameter to fit the G27 slides.
You can not put a standard factory Glock 26 barrel in a G27.
The hole (bushing) in the front of the G27 slide is bigger than the hole in the G26 slide, a G26 barrel in a G27 will slop around.
The aftermarket barrels that convert a G27 to 9mm have the correct outside diameter to fit the G27 slides.
Actually you can install a G26 barrel in a G27 but accuracy will suffer. The reason is the 9mm barrel has a smaller outside diameter then the .40 barrel. Because of this the 9mm barrel will fit too loosly in the .40 S&W upper. It will shoot but it will pattern like a shotgun. The aftermarket drop in conversion barrels have the same O.D. as the factory .40 barrel to correct this problem.
Hammerhead
New member
Those are Warren tactical sights. They have a wide, deep rear notch and a FO front, but they still seem to give decent precision shooting with the 'snubby' Glock.