I have a P226.357 sig complete slide (legacy, no optic cut) and I am wondering if I can shoot it in my P226 9mm legion slide (optic ready) with just a barrel and recoil spring change?

I've been told that the non-optic slides are too thin to Mill an optic cut and those optic ready slides are actually part of the forging process.

The weight of the 9mm slide is somewhat less than a 357 SIG (& 40 S&W) slide. That would result in higher slide velocity and battering of the frame even with a stronger recoil spring.

The main problem, though, is that the breech face of the 9mm slide has a narrower slot to accommodate the 9mm cartridge case head. A 357 SIG cartridge will not fit into that slot. You can confirm that by seeing how a 357 case would fit the 9mm slide.

Years ago I had a P226 slide (357/40?) milled to accept a Docter red dot sight. The milling cut far enough to expose the safety lock spring opening. The slide was usable that way, but only with the sight mounted.

Hey thanks for reply, explanation. I might poke around again at milling the slide.

The truth is, I have a love relationship with the 357 sig ever since it came out. I have a P239 in it and the P226 slide I bought years ago.
I reload, and have booqu components for the cartridge, so I want to keep shooting it as well.

At my age, iron sights just ain't getting it done, I've switched over and I really shoot alot better, especially at distance.
Thanks again

Yes, the 357 SIG is the king of cartridges in its class. But as with most things in life, people get what they want, and therefore what they deserve. As I like to say, if I’m ever shot, I hope it’s by someone who believes in “Good enough.”

If you really want to convert to .40/357SIG P226 from 9mm, know that P226 frames are the same for all 3 calibers, and magazines specific to those calibers fit in all the P226 frames equally.

I'd get a .40/357 P226 slide/barrel/recoil spring/magazines if I wanted to shoot those calibers.

Milling a 9mm slide to me seems like the expensive/time consuming/wrong way to the same goal, when .40/357 slides aren't worth that much and can be found.

EGW makes a red dot mount that uses the rear sight dovetail.
I have no experience with it but probably worth trying before machining the slide.
EGW mount

Austin228,
I did mention I have a complete 357 sig slide.
Sigfreud has already answered my question about just using a 357 barrel and recoil spring in a 9mm, not gonna do it.
I am now looking into having my complete 357 slide milled for an optic.
Thanks for your response.

Nukeandpave,
That is an interesting mount.
I wonder if the optic sits that much higher than milled?
As you know, the P226 already has a high bore axis.
I'm really partial to the Holosun 507 Comp as I have several and I'm not sure that's one that can use this mount?

quote:

Originally posted by sigmoid:
I wonder if the optic sits that much higher than milled?
As you know, the P226 already has a high bore axis.

Yes to both. By nature of their designs, you can't make an optic cut fit as low on a hammer gun as you can on a striker gun. I have a dovetail optic mount for Glock, and I can feel the difference between it and my optic-cut Glocks.

quote:

I'm really partial to the Holosun 507 Comp as I have several and I'm not sure that's one that can use this mount?

507 Comp uses RMR footprint and should be compatible w/ that EGW mount. You could always email EGW to confirm.