Safety / reliability of 9mm conversion barrels in .40 cal Glocks?

[Byron]

A friend of mine just purchased his first Glock; a Gen4 23. He has also purchased a LWD conversion barrel so that he can shoot 9mm when he wants. When he mentioned this to the gun shop employee, he was told that he was "taking his life into his own hands" and that he ran the risk of "blowing out the side of his pistol."

Is there any merit to the claim that a 9mm conversion barrel in a .40 Glock is actually dangerous?

My friend is willing to accept that the pistol might not run as reliably as a stock 9mm, but he obviously doesn't want to risk injury. So what are your thoughts? Is this a valid concern, or just gun shop hyperbole?

[ToddG]

Anything is possible, but catastrophic destruction isn't something I'd consider more likely with a conversion barrel than a same-caliber aftermarket barrel from the same manufacturer. Your friend may simply have found the one gun shop employee on Earth who is ignorant and/or prone to hyperbole.

[Byron]

Thanks for the quick response, Todd!

Your friend may simply have found the one gun shop employee on Earth who is ignorant and/or prone to hyperbole.

Hahahahaha - excellent

[Tamara]

Your friend may simply have found the one gun shop employee on Earth who is ignorant and/or prone to hyperbole.

Phhhhth! There are at least a billion gun shop clerks that are prone to hyperbole!

[ToddG]

Phhhhth! There are at least a billion gun shop clerks that are prone to hyperbole!

Hypocrite. I bet there aren't half that many.

[GJM]

Any other parts that would need to be changed for best function, and would you expect this barrel in a 40/357 to be as reliable as a regular Glock 19? Reason I ask, is I have a like new Gen 3 OD Glock 32 in a corner.

Glock experts, should a Glock 20 10mm factory or after market barrel work in a Gen 4 Glock 21?

[WDW]

Any other parts that would need to be changed for best function, and would you expect this barrel in a 40/357 to be as reliable as a regular Glock 19? Reason I ask, is I have a like new Gen 3 OD Glock 32 in a corner.

Glock experts, should a Glock 20 10mm factory or after market barrel work in a Gen 4 Glock 21?

You can stick a .40 oem barrel in a G32 no problem & vice versa. The 32/23 are the same gun. Whatever you do, DO NOT STICK A G20 BARREL IN A G21. You will not like what happens. The G20/21 use the same frames, so a full slide swap is ok, but the slide masses are different to handle the higher pressure of the 10mm. Also, the G20 barrel will not fit correctly because it is .40 caliber dimensionally whereas the G21 is .45. All that combined, & you are just begging for a bad kB!!!!! If you try it.

[Magsz]

There are breechface difference which can cause a live 9mm round coming out of a .40 conversion barrel to hit the straight .40 cal ejector and result in a detonated primer. Firing out of battery like this is bad juju.

The likelihood of this happening is slim to NONE but the possibility still exists.

I BELIEVE that lonewolf drills the chambers off center to account for this in their barrels but i might be wrong on that one.

For a game or fun gun, by all means, run them. The chance of this happening is probably the same as actually having a KB which you cant control (generally). For serious purposes, play it safe and dont run conversion barrels on defensive firearms.

[JBP55]

Every non OEM barrel I have used worked 100% just like my Glock barrels.

[JDM]

Every non OEM barrel I have used worked 100% just like my Glock barrels.

How many different barrels, and how many rounds?