When the P239 was made available in .357sig, did the original mags have the narrowing to support the shoulder of the necked round or did they have some combo .40/.357 mags.

I just ordered a couple .357sig mags already knowing .357sig works fine in my .40 mags but I just wonder if the difference was to solve a problem or to avoid a non-existing problem.

To my knowledge they offered caliber specific mags from the beginning.

All my various Sig mags have always been marked 40/357

IIRC, there are 40/357 mags & 357 only as well.

I've been telling my dad for years to pick up a 357Sig bbl for his 239.

All the P239 magazines I have are marked “.357 SIG” or “.40”, not both. Were there ever any that had both cartridge markings? Possibly, I suppose, but mine date from when I purchased my 357/40 P239 in 2006.

quote:

Originally posted by walker77:
All my various Sig mags have always been marked 40/357

I have those in my 229s, but my P239 .40 purchased in 3/2001 is marked .40, although .357sig works fine.

I think my dad's '96 [or so] 239 mags are marked 40/357, but its been a while.

I have two P239s both 357 SIG and all the mags are specific to 357 SIG.

What're you trying to do?

I've owned several 239s in 40, 357sig and 9mm. To my knowledge their magazines have always been marked as caliber specific.

quote:

Originally posted by Nev:
What're you trying to do?

I'm trying to determine if it's safe (or someone deemed it unsafe) to shoot .357sig out of .40 mags.
I *thought* I read some time back that the narrower mags allow the case shoulders of the .357sig to be supported by the walls of the mag, preventing bullet setback during recoil.
If true, I should have the .357 mags when I swap barrels. If not, why would they bother to do this except for maybe reliability.
Does it increase reliability for the .357 for self defense purposes? I don't know.

My 229s don't have a problem using the same mags and are labeled for both.

Like others have posted, my P239 mags are also caliber specific for either 357Sig or 40SW, not both.

If I remember right, the 239 had different magazines for .357 and .40. There was an indention in the magazine to better control and feed the shorter bodied .357 case, it didn't have anything to do with setback to the best of my knowledge and I don't see how a magazine could prevent it in any case. .40 rounds won't fit in a .357 magazine but .357 will fit in a .40. Some of the early 239s supposedly had a different magwell that would prevent .40 magazines from fitting into a .357 pistol, but I've never seen such. That doesn't mean it doesn't exist as I haven't handled many guns originally chambered in .357. I've owned 4 p239s over the years, but they've all started out as .40.

I've got a good friend who has put a ton of rounds of .357 through a 239 with the "wrong" magazine and never had an issue. I guess I'd fall in the camp that if Sig engineers decided a different magazine was needed for reliability and said magazine was available, I'd get a few for my carry mags. I'd have no concern using the .40 magazines for the range or if .357 weren't available.

FWIW: I bought a P239 in .357 Sig when my department only approved carry of .40 S&W, 9mm, and .45 ACP calibers. I switched out the barrel for a .40 S&W barrel and used .40 S&W magazines without issue. Later, I fired .357 Sig ammo using the .40 magazines and found (with the .357 barrel installed), it functioned perfectly. Still later, I obtained a 9mm barrel, swapped out the heavier recoil spring for an appropriate one, and fired 9mm ammo using the .357 and .40 S&W magazines. Not only did the pistol function 100%, in it's 9mm configuration it was more accurate than as a .40 or .357 Sig.

I've shot 9mm out my .40 mags w/ the original .40 recoil spring. I've since replaced that spring but keep it in case the fresh spring produces problems for the 9mm.

In closing, I guess my original post had me wondering if I really needed 9mm and .357 mags if the .40 mags work fine.
Since future production of the mags is not certain, I grabbed some of each.
At a minimum, I should have them if I choose to carry them for defensive purposes.

I've never tried to use 9mm in the 40 or 357 mags... may be worth a try... keep in mind of one other item... the base of the P239 is a different size between the 9mm ones and the 40/357 sig ones... 40/357 sig mags will not go into a 9mm P239 grip. But 9mm will go in the larger caliber one.

My take. The 239 was designed for Air Marshals , Secret Service LEO. This was not designed with the civilian in mind.

There was never a 22 conversion, a rail.... etc {I'm more surprised that any were made without the SAS marked on them, since there is little difference between the SAS marked ones and non SAS marked ones}

The bottle necked 357 Sig and it's reliability was the purpose for a dedicated mag. Not because the 40 mag wouldn't work, but because this was designed for the elite security forces and reliability was a major issue.

This was not designed as a civilian gun. {DAK is rather common too}

It was made for concealed carry as an ultimate.

Weight enough for control,{Never offered in a stainless frame} light enough for carry, short grip for conceal-ability. OH.... and a bit of power.

I love mine!

The P239 has caliber specific mags and always has. Its always been understood that 357 can be shot out of 40 marked mags without issue but not 40 out of 357 marked mags.