I have a SIG P229 in 40S&W caliber. I am wondering if I would have to change anything else but the barrel to set it up for 357 SIG?
Jim

A barrel change alone should be sufficient. I have done that with a SIG P226, and it seems to work fine with the same 20# recoil spring.

357 SIG rounds feed reliably from a .40 magazine. The body of the cartridge is the same size, but the neck and bullet smaller. Feeding is enhanced by the bottleneck configuration. If this is a self-defense weapon, most recommend you purchase dedicated 357 SIG magazines. (If you "convert" a P239, dedicated magazines are required.)

Examine your reasons for the conversion. 357 SIG ammunition is expensive, hard to reload, and has limited options. Are you willing to pay a premium for practice? The penetration is somewhat better than .40SW, but it's questionable whether it has more knock-down power. I find the recoil similar between the two, and in no way difficult to manage. 357 is definitely louder.

The barrel is all you need to get it done. I did it to my P229Elite and haven't looked back. It's one of my primary duty weapons. It runs 100%.

I find the recoil of the .357sig to be snappy, but much more controllable than .40s&w. I keep the .40 barrel for practice because ball ammo is much more available, and then for all duty related work it's the .357sig. Ballistically, the .357sig is far superior. I've done a fair amount of homework on it and the studies from Dr. Roberts, plus a pile of autopsy reports, show it.

The only downside is ammo availability. Other than that, it's a no brainer for me at least.

Thanks for your replies. I have re-loading dies for this caliber and I feel having a pistol with two different caliber options is a good situation.
Jim

Like others have posted, all that is needed is the 357sig barrel. The magazines are the same for the P229 and many are even marked .40S&W / .357

(hard to see in this picture, but trust me - it's there!)


However, one thing to keep in mind are the sights on the gun.
Sig uses #8 sights on the front and the rear on guns chambered in 9mm and .357sig.

They use and #8 on the rear, and a #6 on the front on guns chambered in 40S&W and .45acp

Your POI (point of impact) will start to change as you shoot at further distances with the .357sig barrel due to the size #6 front sight of your gun that was originally chambered in 40S&W

__________________
Rick
SWCA #2727 , SWHF #435

I have an older 229 in 357 Sig, it is a 1990s LE gun and the mags are marked 40 and 357 as are the later 10 round only mags from the bad old ban days. It isn't that hard to reload, just don't try FMJ/RN, use something with straight sides like a HP or a truncated FMJ. My gun is most accurate with hotter loads. Ivan

Mine has the built in laser sight in the guide rod so I'll have to see what adjustment is necessary. Again thanks for the help.
Jim

My DIL has a P-229 in .357 SIG and likes it very well.

Texas DPS and other police find the load works very well in real life shootings. If I had to carry an auto at work and the option was offered, I think I'd carry a P-226 in .357.

Not a fan of either .40 or .357sig as I already had "enough" .9mm and .45s. Throw in revolvers and my ammo life was already complicated enough......LOL

Something to consider...........

After the craziness of 2008-09.....................

Several years ago I picked up a real nice used 229 with both the .40 and .357 barrels and 3-4 mags. at a good price. I've added a couple more mags.... and I was good to go in either caliber if I could only find .357 sig or .40S&W ammo. The gun fit holsters for my Sig 245.

Jan- April/May of 3013 ..... panic in the gun shops....... the only ammo that was readily available in the LGS and box stores around here was .357sig. Still going for IIRC about $23-25 for a box of 50 hollowpoints. So I added a couple hundred rounds to my stash!!!!

Thread drift.
If I were starting out now, I'd probably go with the 40 S&W; it's more powerful than the 9 but comes in a lighter package than the 45, etc, etc.

But, I have someting like 12 pistols in 45, a 50 cal ammo box full of ammo and another full of brass waiting to be reloaded; dies; at least two 4 cavity bullet moulds, and about 40 years of loading data. I also like the way a 45 feels in my hand.

I have the same thing in 9mm (maybe 15 pistols and 45 years of data). I don't think I need to get into an auto pistol caliber in the middle.