A little Glock help please.

[deadcoyote]

I have a Glock 31 (full size 357 sig). I own an LWD aftermarket .40 SW barrel to shoot cheaper ammo. I do not care for the LWD barrel that much, the factory barrel is much more accurate. I am now looking to buy a 9mm barrel and some mags to shoot even cheaper ammo. Will a factory Glock 17 barrel fin in my Glock 31 (outside dimensions)???:confused:

PS, I'm on a budget, so I'm not going to buy a super doop aftermarket barrel. I was disappointed in the LWD and would like to stick with the good ol' Glock parts if it'll work.

[rjrivero]

I have a couple Lone Wolf Barrels and they do just fine in my Glocks. I'm sorry to hear you're having an issue with them.

I wouldn't recommend using a Glock 9mm barrel in your 31. They just don't fill the cut out in the slide very well. You'll really need a conversion type barrel.

[deadcoyote]

I will give the LWD folks full credit for offering a functional, affordable product. From my personal experience, I have found that I can shoot approximately three times tighter groups at any given distance with the factory barrel versus the LWD drop-in. Perhaps I simply lucked into an especially well fitted factory barrel and conversley fell into an especially poor fitting after-market set up. I can't personally say, I'm not a gunsmith. I just know what works and what doesn't!

[AK103K]

I have a LWD 9mm barrel for my 31. Its been 100% from day one, and accuracy is as good or better than the 357 barrel that came with the gun.

[SigP6Carry]

I'm pretty sure that the 9mm Mags will fit in the .40 and .357sig frames. It's the barrels that I'm sketchy on.

It's been a while since I've researched Glocks (it was almost a year ago I decided to go Sig), so I can't quite recall for sure if my information is 100% correct.

[AK103K]

The 9mm mags work fine in the .40/.357 frames.

[Crapulence]

I have a g31 and also got a lonewolf .40 barrel. I have similar accuracy issues, it is my uneducated guess that the lone wolf barrel is fine its the .40 cal round that is lacking the accuracy. My g31 is the most accurate pistol I have. I find this a bit of a surprise, I thought that Glock left a fair amount of slop in the actions to help with reliability.

[Ksmoker]

I put the LWD barrels in a 31 & 32 but stayed with the .357, I don't shoot as much as some of you, I don't have the time or the budget to get down to splitting hairs that some do in comparisons. I've not had any problems with the aftermarket barrels, I do roll my own to save the change along the way. It occupies a lot of time for me in the winter as well.

[voyager4520]

To answer your question, no. The outside dimensions are different. You need a .40-9mm conversion barrel which has the outside dimensions of a .40/.357SIG barrel but is designed to shoot 9mm.

You can drop a factory .40SW barrel into your G31, but not a factory 9mm barrel. Since a .357SIG Glock is simply a .40SW Glock with a different chamber, you would use a .40SW-9mm conversion barrel to convert your G31 to 9mm.

You will also need Glock 9mm magazines of course, G17 magazines.

Because 9mm conversion barrels are intended for cheaper shooting at the range none of them have polygonal rifling. If someone is looking for cheaper shooting, they might want to shoot unjacketed lead to cut down on cost. Unjacketed lead should not be fired through barrels with polygonal rifling, so every aftermarket conversion barrel I've seen uses conventional rifling.

Also take notice that converting to 9mm with an aftermarket conversion barrel will not give you 100% reliability so it should not be used for carry/self defense, only cheaper shooting at the range. Converting between .40 and .357SIG however with the appropriate magazines should be just as reliable since all Glock did to make their .357SIG pistols was to take their .40SW pistols and put different barrels in them and different followers in the magazines.

[AK103K]

Also take notice that converting to 9mm with an aftermarket conversion barrel will not give you 100% reliability...
This may be on a gun by gun basis. My 31 with the LWD 9mm barrel in it has never missed a beat, and I've got a good number of rounds through it now.

I've seen the same thing posted in a couple of places about the reliability issues, and have been told I would need to change out the extractor and ejector as well, but so far, mines been 100% with just a barrel change and my 17 mags.

I would think if the gun doesnt give you any troubles, youre probably OK. I'm sure you'll know if your not.