today I went to my gun club and decided to try something...

As we've discussed, You can put a 9mm barrel in a P239 pistol designed (slide & grip) for 357sig and it will work... 9mm will fire and eject with just the barrel change out...

so, I was wondering about the same thing with a P226. First 357 sig magazines will not work.. the 9mm rounds pop out when you try to load them... so, you have to use 9mm magazines which of course work/fit in all the P226's including 40 cal and 357 sig... lower frames are the same both DA/SA as well as SAO. Using the 9mm mag then I put a 9mm barrel and recoil spring in the slide designed for 357 sig and tried it out... put about 10 rounds through it with no problems.. then I removed the 9mm recoil spring and traded it for the 357 Spring and got the same result.... I'm pretty sure you can't do the opposite... 9mm slide to 357 or 40 with just a barrel change... the ejector part in the back is sized smaller for 9mm .. also the 9mm slide is actually slightly lighter than the 357/40 sig ones...

Oh, I only used 9mm 115 grain fmj rounds and so possibly heavier rounds might not do the same.

From what I recall, you can basically do that, though I heard you needed a 9mm conversion barrel. I'm guessing it has a slightly larger outer diameter.

Still, if it worked for you, awesome!

Good question but the answer is the outside diameter of the two barrels is the exactly the same. I just checked.

Now what is different is the actual weight of the two slides...

9mm slide with barrel and spring is: 16.9 oz

357 slide with barrel and spring is: 18.0 oz

The breechface is 40 caliber size, so the extractor and ejector geometry are not ideal.

Range gun at best.

quote:

Originally posted by Blume9mm:
Good question but the answer is the outside diameter of the two barrels is the exactly the same. I just checked.

Photos would be nice. Not that I doubt you but just to satisfy or prevent further argument.

quote:

Originally posted by bubbatime:
The breechface is 40 caliber size, so the extractor and ejector geometry are not ideal.

Range gun at best.

I agree totally. I just wanted to see if it would work and also post here to see what others thought and if there was some potential issue with it. Now I wonder if a heavier bullet would make a difference.... as I said, I was shooting 115gr fmj ammo.

Can't see how a photo or photos are going to help... they won't show anything. there is no visible difference between P226 9mm slides and the 357/40 ones other than the weight and the diameter of what bubbatime called the breach face... the indented section that covers the back of the cartridge when locked in the chamber and has the firing pin in the center of it. You would think because the ejector is on the side of this that there would be a problem with ejecting 9mm rounds but at least for the few rounds I shot there isn't. Same thing I found out with the P239 which is why I tried it on a P226. the only difference is 9mm rounds won't work in a double stack 347/40 magazine. Seems they will in the P239 single stacks.

Oh, I just re-read what dslets was asking for... I may do that but would have to do with the the calibers showing the two same sizes... actually, just to double check I just measured the hole in the front of the slides that the barrels protrude from when firing and they are the same... actually if there was going to be a difference it would have to be for the 40 cal. since 357 sig is still 9mm and only the rear chambering of the barrel is different to accommodate the necked down 10mm cartridge. I guess the difference is the 40 cal barrels are thinner with a larger hole. Yep, just checked.

I'm by no means a machinist... but my father was one for over 40 years and he left me a couple sets of his calipers and that is what I'm using to measure these things with... they are measure down to a thousands of an inch. Example... both the 9mm and 357 barrels are .355 inside diameter and the 40 cal... guess what? yep... .400

A Bar-Sto Semi-Fit 9mm conversion barrel is what you need.

I've done the same thing with my P-229 .357 Sig/.40 S&W. You'll use the same recoil spring, but will need to take your pistol and Bar-Sto barrel to a gunsmith so the barrel can be precision fitted.

Robert Burke here in the DFW area did mine, and it works flawlessly.

Still don't understand why one would need a conversion barrel...

but I did not run a lot of ammo with my test and I'm not one to run a lot of ammo when I go to my gun club... but I am in three weeks going to a two day handgun class and will probably come close to shooting 500 rounds ... I may just take the 357 slide with me and put the 9mm factory barrel in it and see how it goes...seems the worse that is going to happen is I will have failures to feed and then I'll just switch back to the 9mm slide. Seems to me the slightly heavier slide might help with recoil and recovery to getting back on target...

Blume9mm, please do that and let us know how it goes. I run a regular 9mm barrel in my P239 .357 Sig and it works fine. I have never had a failure in probably 400 - 500 rds of 9mm. Based on that experience, I have also wondered about converting my P229 .40 with just the regular 9mm barrel.

quote:

Originally posted by Blume9mm:
Still don't understand why one would need a conversion barrel...

I believe the top lug of the chamber area that interfaces with the breech face cutout in the slide is wider on a conversion barrel. Maybe it still doesn't matter, but you're accepting an imprecise fit in a fairly critical area.

quote:

Originally posted by shoe303:
Blume9mm, please do that and let us know how it goes. I run a regular 9mm barrel in my P239 .357 Sig and it works fine. I have never had a failure in probably 400 - 500 rds of 9mm. Based on that experience, I have also wondered about converting my P229 .40 with just the regular 9mm barrel.

Shoe303: I don't think the P229 is the same as the P226 but don't know for sure, I only have P226's and P239s....I know the slides are different on the P320s and P250's and you can't just change out 9mm and 357 or 40 barrels in those.

DaBigBR: I fixing to take measurements on all that too.
Update: you are right! as you called it, the top lug on the barrels are a different diameter and the corresponding gaps on the slides correspond.; .433" on the 357/40 and .408" on the 9mm.
Now I need to check this on my P239's

yep, same on the P239s

Here's some information, forgot where I got it from but some may find it useful. I bought a 9mm threaded barrel for my .357 P226 and it drops right in, shoots fine. Used it in my .40 P226 Tacops and works in it too. Just have to use 9mm magazines of course.