I picked up a LE trade-in P226 in 357 Sig and wanted to convert it to 9mm.

Anyone have any experience doing so? There's a lot of conflicting info out there. Some discussions seem to say you need a specific conversion barrel, other people say all you need to do is drop in a standard 9mm barrel and swap the recoil spring and you are good to go.

What do the experts here think?

quote:

Originally posted by tau-neutrino:
I picked up a LE trade-in P226 in 357 Sig and wanted to convert it to 9mm.

Anyone have any experience doing so? There's a lot of conflicting info out there. Some discussions seem to say you need a specific conversion barrel, other people say all you need to do is drop in a standard 9mm barrel and swap the recoil spring and you are good to go.

What do the experts here think?

I'm no expert, but I've had nothing but success with a Bar-Sto conversion barrel, 9mm recoil spring and 9mm magazines in the P226 (Elite, and X-Five) and P229 (Elite).

There is one Sig pistol (P239 ?) that has the same outside diameter (OD) for 9mm, .357 Sig, and .40 S&W barrels, but for most Sig Sauer pistols, including the P226, the OD of a factory drop in 9mm barrel is smaller than the OD of a factory drop in either .357 Sig or .40 S&W (which both have the same OD and are interchangeable).

Two options for converting a .357 Sig P226 to 9mm are a) buying a conversion barrel and b) buying a factory caliber exchange kit, which comes with a 9mm upper (slide, barrel, recoil spring and guide rod assembly, and a 9mm magazine.)

The former option is cheaper, the latter gives you an essentially factory 9mm as well as a factory .357 Sig that is as simple to change back and forth as swapping uppers and magazines.

From experience, I can tell you that you can run .40/.357 Sig magazines with 9mm ammunition in a P229 and I’d assume the same is true with a P226. I did discover that factory 10 round .357/.40 magazines will hold up to 13 rounds of 9mm. I can also tell you from experience that while they are pretty reliable with 10 rounds of 9mm, they are a little less reliable with 12 rounds of 9mm, and pretty unreliable with with 13 rounds of 9mm. The 226 magazine shape is different and it may not suffer from this issue.

I suspect which option makes more sense to you and whether you want to buy 9mm magazines will depend on your intended use and perhaps your budget. For a range toy, you may decide, “What the heck, save a few bucks, do it as inexpensively as possible and see how it works. Worst case you get plenty of immediate action drills. If it is to be a defensive pistol in 9mm, you may opt for the later choice.

Whatever you choose, have fun. It is a great pistol in both (heck all three) calibers.

Btw, if you also have interest in .40 S&W, a simple factory .40 S&W barrel and you’re good to go. .40S&W and .357 Sig use the same slide, recoil spring, and magazines.

quote:

Originally posted by slosig:
[F]or ... the P226, the OD of a factory drop in 9mm barrel is smaller than the OD of a factory drop in either .357 Sig or .40 S&W ....

No, not true.
The only obvious size difference between P226 9mm and 357/40 barrels is that the barrel hood extension of the latter is very slightly wider than that of the 9mm’s. A 357/40 barrel will therefore not fit into a 9mm P226 slide. (The barrel of the 357/40 P229 is indeed larger in diameter than that of the [original] 9mm P229 or P228. I don’t know about the P229-1.)

On the other hand, a 9mm barrel will fit into a 357/40 slide although there is the possibility of a tiny bit of side to side play due to its narrower barrel hood extension.

Although I have not tried it myself, I have read several accounts of people successfully using a P226 9mm barrel in a 357/40 slide and frame. It isn’t ideal or of course sanctioned by the factory, but it reportedly works. Better would be to use a proper 9mm slide assembly or at least a 9mm conversion barrel.

Please tell me you shot the 357 first!

quote:

Originally posted by flesheatingvirus:
Please tell me you shot the 357 first!

Not yet...just picked this guy up today, but I've got a few boxes inbound.

The previous owner did not love this gun like I will though, rust in a few spots and oh so much dirt caked inside. The trigger pull is actually gritty as is the decoker, and even just pulling the hammer back manually. It needs a good detail strip for sure.

Watch Broker for a "226 9mm parts kit". they show up with regularity and often include almost every part but the frame. Yes, they're used parts, but so is the gun you bought. Its a cheap way to get a pistol conversion kit that lets you switch back and forth without anything more difficult than switching uppers and mags. I have one 226 that has the factory 9mm upper, a second in .40, and a .22 conversion kit. a great SHTF package of need be.

Wouldn't the extractor have to be larger to make up the difference between the 2 cartridges? They may be built to work with both. Just wondering.

quote:

Originally posted by tankeryanker:
Wouldn't the extractor have to be larger to make up the difference between the 2 cartridges?

Extractors for Classic line SIGs are a confusing issue for me. Originally there were different (short) extractors for the various pistol models and cartridges. More recently I seem to remember seeing an indication that the different versions had been merged, but I don’t remember any details. In practice, however, as long as I’ve seen discussions of conversions between 357/40 and 9mm, there have been little, if any, claims that not switching extractors made any difference in reliability. (The same, BTW, is also true of the ejectors; at one time at least, 9mm and 357/40 P226 ejectors had different part numbers, but I never heard of anyone switching parts when making conversions.)

And as far as I can determine, the pistols that now use the long external extractor all use the same part.

I think there is no problem doing this.... actually all you need to do is install a 9mm barrel....

What you say?

I took the 9mm barrel out of my standard Sig p226 and installed it in my Sig P226 legion that came as a 357 sig... kept the 357 recoil spring and rod in and even used the 357 magazines..... guess what? the pistol functioned fine.. and shot great!

Same thing happens with P239s.

quote:

Originally posted by Blume9mm:
I think there is no problem doing this.... actually all you need to do is install a 9mm barrel....

What you say?

I took the 9mm barrel out of my standard Sig p226 and installed it in my Sig P226 legion that came as a 357 sig... kept the 357 recoil spring and rod in and even used the 357 magazines..... guess what? the pistol functioned fine.. and shot great!

Same thing happens with P239s.

Great, I find this out after I ordered a a 9mm recoil spring and two new magazines....hahaha.

Good to know!

I guess in the 'smithing' world would be the question as to if the slide on the 357 is different than a standard 9mm.... I don't think there is but am going to go weigh and measure(to a degree) both.
the slides are different on P239s.

I was surprised that the recoil spring for the 357 barrel functioned fine with a 9mm barrel...but it did.

I'd like to find a basic / standard barrel in 9mm for both a P226 and P239 so that I would not have to remove one from a gun to do the change out when converting my 357 sigs.

Edit: I just did some checking....

9mm Slide (barrel, spring and rod removed): 12oz/ 341 grams
357 Slide (barrel, spring and rod removed): 13.1oz/ 373 grams

9mm recoil spring & rod: .6 oz, 19 grams
357 recoil spring & rod: 1.3 oz, 38 grams

there is a difference in the distance between the extractors.... 9mm is slightly closer in.

The differences between 357/40 and 9mm P226 slides can be seen just by a cursory examination of their undersides (at least that’s true of the guns I own). I believe it’s obvious that the former are heavier because 357 SIG and 40 S&W are more powerful cartridges. A heavier slide has more inertia and coupled with a stronger recoil spring that reduces the battering effects of the recoil. I also believe that part of the design consideration was the fact that different 9mm loads vary far more in power than is common for 357 and 40; shooters want to be able to use everything from wimpy 115 grain powder puffs to extra hot 127 grain +P+. Then there is the fact that the designers probably don’t want the company having to deal with complaints that a gun stops working merely because it hasn’t been cleaned for six years and 5000 rounds fired. All that requires balancing among the pistols’ features.

It doesn’t hurt if a 9mm barrel fits into a 357/40 slide and someone shoots the gun like that. If it doesn’t work for some reason no one will have a legitimate complaint and if the shooter calls SIG customer service about it, that merely gives the rep something to chuckle and shake his head about. On the other hand if someone could shoot 357 or 40 ammunition with a lighter 9mm slide and its less powerful recoil spring, that could result in premature failure of the frame rails. “Hey, SIG: Your crappy gun broke; I want a new one.”

Yep, to above.. on my p239s there is a significant difference between the two slides....

What I'm doing, just to be cheap, is to try and use 9mm rounds...(wimpy 115grain ones) in my carry pistol just for practice.... so, as far as I can see (up to date) there is not problem just slipping a 9mm barrel in.... but then I could be wrong (I was once before)