is there a list somewhere of what actually fits and works? I thought I understood you needed a Leupold DPPro but then I just saw a picture of something else mounted, so now I am unsure. I wouldn't normally have bought one, but my love of poop colored guns overcame me. TIA.

Currently, the DPP is the only “direct fit” option.
If you can source the appropriate head size and length M4-0.7 screws, you could mount a Romeo 1, Shield RMS or JPoint red dot, but they will not “fill” the slide cut (cosmetic) or hold the loaded changer indicator in-place.

The Romeo 1T (when/if released) is said to fit. If it doesn’t make it to market, I would think Sig would offer a M17-specific mounting kit for the current Romeo.

The deltapoint pro is the only one.


You can put a romeo-1 on if you drill out the screw holes in the optic to accept the larger screws that the Leupold uses. They have the same spacing on the screws holes, just different diameters. The romeo is also shorter by a smidge.