My P226 is chambered in 357SIG but I wanted to convert it to 9mm to take advantage of cheaper and more available ammo. After researching on here and elsewhere, I determined that there were three basic approaches:

Cheap/questionable ($200): buy a standard 9mm barrel ($180), weaker recoil spring ($20), use the 357SIG magazine and give it a go. Some owners have reported success with this approach, but it’s reliability would be suspect for personal protection.

Full-on SIG recommended approach ($630): buy a standard 9mm barrel ($180), weaker recoil spring ($20), 9mm slide ($380), and 9mm magazine ($50). This is basically totally recreating your gun, and it should function as if the P226 was purchased as 9mm originally.

Drop-in barrel ($320): buy a Bar-Sto 9mm “drop-in” barrel ($250), weaker recoil spring ($20), and 9mm magazine ($50). This provides fully reliable functionality at roughly half the cost of Sig’s recommended approach. If used exclusively for the range, one could also likely get by with the 357SIG magazine (user experiences vary).

I went with the drop-in barrel approach. Incidentally, Bar-Sto cautions that sometimes light machining is required to fit the barrel to the slide, but 75% of the time no machining will be required. Mine fit fine as it came.

BTW, thanks to forum members who did the heavy-lifting on this topic. I simply researched, priced out, and restated what I found. I suspect that a .40 to 9mm conversion would be exactly the same.

quote:

Originally posted by RickinAZ:
I suspect that a .40 to 9mm conversion would be exactly the same.

I'm glad you posted this summary.
I've wondered what it would take to convert a .40 P226 to 9mm for range days or matches, and if the cost would be worth it.

If all you do is slap a 9mm barrel/spring in the .357 Sig, you have a 9mm cartridge case trying to latch onto a .40 cal (10mm) breech face. There is 1mm of slop there...will that fire/extract/eject reliably every time?

There’s another route as 226’s share the exact same frame; watch broker and look to pick up a “parts gun kit” that has all the parts save the frame. Get one with a complete slide assembly and simply drop in the 9mm assembly and go shooting.

quote:

Originally posted by 229DAK:
If all you do is slap a 9mm barrel/spring in the .357 Sig, you have a 9mm cartridge case trying to latch onto a .40 cal (10mm) breech face. There is 1mm of slop there...will that fire/extract/eject reliably every time?

I think you hit on the part that makes it questionable and unreliable for personal safety, but some Sig owners have reported that it works. Seems a little slapdash to me.

quote:

Originally posted by gearhounds:
There’s another route as 226’s share the exact same frame; watch broker and look to pick up a “parts gun kit” that has all the parts save the frame. Get one with a complete slide assembly and simply drop in the 9mm assembly and go shooting.

Search for "P226 repair parts" on GunBroker instead. You'll find listings from companies that destroy guns for law enforcement and sell every part together except the destroyed frames. There are currently 2 auctions open right now that end on Saturday. One for a .40S&W set of parts and one for a 9mm set of parts. Just make sure to not run the bidding up to more then the cost of the parts you want seperately.

You can also search for "P226 complete slide assembly" if you're looking for a slide, barrel, recoil rod and spring that are new parts.

Several years ago, I went the full Sig-approved route and bought the conversion kit. I have .357/.40/9mm. As you'd expect, it works perfectly.

I have three P226s - one in each caliber. I stumbled upon a cheap, used Bar-Sto threaded barrel in 9mm and grabbed it. It works fine in my .40 and .357SIG P226s.

I did the Bar-Sto approach on a 239. fit perfectly. The barrel was tighter and more accurate than the Sig barrel it replaced.

Worked great for me.

Will a 40/357 slide fit right on my 9mm 226? It’s an older W German frame. Assume just need the mags ?

I have (2) 229 and (2) 228 already that are dedicated 9mm and 40/357 guns

Did you decide what way you're going to go for your conversion? Those P226 9mm repair parts that were on GunBroker sold on Sunday for $366. Every part you needed was in that auction.

Sig Sauer P226 9mm Slide Barrel & Repair Parts

quote:

Will a 40/357 slide fit right on my 9mm 226? It’s an older W German frame. Assume just need the mags ?

Yes. I have a 226 that began life as a .40 that now wears a 9mm milled upper. I also have a folded upper that functions just fine as well. No other parts need to be switched out. Straight drop in and play.

I did the Bar-sto route on my P229 with a P229-1 magazine. I had it out last Tuesday and it was flawless.

I also went with Bar-sto on a P229. At that time it took many months to get the barrel; Bruce Gray helped me with that and installed the barrel; I think the extractor needed to be changed to make it work properly, but it's been flawless (and accurate) since.