Hello,
I am sure this was answered before, but I cannot
seem to find a clear guide on this.

What barrels (link would be highly appreciated)
would one need to get
to add ability to shoot .357 SIG from the P239 .40

and then what barrel (may be form SIG P225A1? )
to shoot 9mm from the same P239
?

Thank you

I don't have the P239, but this is the info I have read.

Shoot .357 in the P239 .40 - Need the factory. 357 barrel. Can use the .40 mag for the .357 ammo.

Shoot 9mm in the P239 .40 - Need a conversion 9mm barrel. Also need the P239 (9) mag.

The 239 is a rare bird.

Get a 40/357 model and have a 3 caliber pistol.
All 239 OEM barrels work in the 40/357 model.
9mm works in 9mm or 40 mags.
357sig works in 357sig or 40 mags.

40/357 recoil spring works for all calibers.
**If you limp wrist, you'll need to change out the recoil spring to a 9mm version when shooting 9mm.

Sig Sauer P239 9mm 8 Round Magazine
https://www.midwestgunworks.co...gwi/prod/MAG-239-9-8

Sig Sauer P239 Replacement Barrel - 9mm - THREADED

https://www.topgunsupply.com/s...el-9mm-threaded.html

This is great info thank you @bigguy!
You are saving me so much hit-and-miss effort!

So for the .357 SIG barrel, what websites
should I check regularly to see it shows up
(I have been checking sig parts for about 8 months, periodically -- did not catch that rare bird)?

Also, thx for the 9mm link, quite steep in price, but threaded! Do SIG p225A1 barrels fit
into the P239, or I am mis-informed on that?

Here’s a better price for the 9mm threaded barrel. https://www.gunbroker.com/item/977544602

For a 9mm barrel I went w/ a true conversion from Barsto.com. They are a bit more $$ and on top of that, they will most likely require a little bit of fitting from your local gunsmith.
https://barsto.com/product/9mm-conversion-p-239/

I've only put a few boxes through mine but it ran perfectly w/ the .40 recoil spring and .40 mags.
I've since installed a new .40 recoil spring so next time I take it along and if it has problems, I kept my older spring and marked it.

I have some NIB .357sig and 9mm mags but if they run fine on the range w/ .40 mags, I'll just continue w/ just barrel swaps.

I have three barrels for both my P239 my first Sig and my P229

They both Came with the .40.

I bought a 9mm conversion barrels from Barsto, back then they were advertising it as a drop-in barrel that may need fitting from a gunsmith.
Mine had to be fitted. It has to be a conversion barrel, the 9mm barrels from Sig are only good for the 9mm guns.

I bought the .357 barrels from Sig and it just dropped in.

Some of my mags are marked .40/357 and work fine.

I bought 9mm mags for 9mm.

It was my carry gun for years and back then I was told 9mm would not run reliably in .40/357 sig mags.

quote:

Originally posted by sig2392:
It has to be a conversion barrel, the 9mm barrels from Sig are only good for the 9mm guns.

You might want to go back and read the thread from the beginning, as your above statement isn't true for the 239.

quote:

Originally posted by Excam_Man:

quote:

Originally posted by sig2392:
It has to be a conversion barrel, the 9mm barrels from Sig are only good for the 9mm guns.

You might want to go back and read the thread from the beginning, as your above statement isn't true for the 239.

^This…

^^^^^^^ Well yes and no but mostly yes.

I and a few others used to be the opposing no vote on the factory 9mm bbl in a P239-40/357 frame and slide.

Although many here are endorsing the use its never been a factory backed conversion.

The reasons being is the square part of the 9mm bbl is smaller then that of the 40/357 bbls which is a loose fit in the slides.

The 9mm mags are also a loose fit in the 40/357 frames.

It used to bother me to no end when the recommendation for using the 9mm bbl was given without a disclaimer to test test and that the possible use could come at a risk in self defense use.

Over the years there have been several reports of the 9mm factory bbl not working for members and to proceed with caution. These threads don't always get those responses nor do I go against the grain with a similar post as I am here.

Me personally I enjoy any gun that I can shoot multiple cal from but the P239 isn't one I would ever use for self defense use.

I consider a true conversion bbl used in a P226 or 229 to be a good true conversion with testing good for self defense use. They have true magazines designed for the rds being used unlike the P239 9mm mags which also fit loosely in the frames.

Also another non factory recommended use of a factory 9mm bbl that some will do is in the P226-40/357 its square part of the bbl is also a loose fit in the 40-357 slide as well as if I am remembering correctly the round part of the bbl OD is also smaller and its use is not factory recommended.

Again if I still owned any P239-40/357 guns i would probably also use a factory 9mm but I would never rely on it for self defense use. I also personally never consider a true 9mm conversion bbl for the P239-40/357 due to the loose fit of the 9mm mags. The conversion bbl gets you there but you still have the magazine differences.


Whatever one does enjoy and test test test.

quote:

Originally posted by 12131:
I don't have the P239, but this is the info I have read.

Shoot .357 in the P239 .40 - Need the factory. 357 barrel. Can use the .40 mag for the .357 ammo.

Shoot 9mm in the P239 .40 - Need a conversion 9mm barrel. Also need the P239 (9) mag.

You'll need a 9mm recoil spring for the heavy (.357 Sig/.40 S&W) slide to work reliably in that caliber.

I bought my P239 as an OEM .357 Sig, but my department's policy didn't' allow that caliber, only .40 and 9mm. Replacing the .357 barrel with the .40 worked fine, but when ammunition availability/cost became issues, I picked up a 9mm barrel and recoil spring. In 9mm, not only did it reliably shoot that caliber using .357 and .40 caliber magazines, it actually shot the rounds more accurately than with either of the other caliber barrels. I don't carry/shoot this pistol often, but when I do, I do so in the 9mm conversion. The perceived recoil and muzzle rise are noticeably reduced. Here's a pic of my set up and the optional equipment.

If you compare the 9mm conversion barrel to the 9mm OEM barrels there are visible size differences.

What anyone else does is up to them.

Sig doesn't recommend it, at the time they did not sell conversion barrels. I have no idea if they do now.

I would have bought 4 barrels from them instead of two.

They recommended I go somewhere else for my conversion barrels.

Good enough for me.