When I bought my Sig Sauer P226 MK25 9mm pistol (commonly referred to as the “Navy Seal” gun), I had no idea that finding a concealed holster to fit would be so difficult. I really like the Blackhawk SERPA CQC holster, but web searches could never definitively tell me if it would fit. So, after purchasing the SERPA holster for the P220/P226 (part number 410006BK-R), I can now confirm that the P226 MK25 will not fit this holster — even with the retention screw completely loosened.

The problem is that the accessory rail on the MK25 is a true (i.e. flat) M1913 Picatinny rail, as compared to the curved Sig Rail on most other P226 models. Here’s a side-by-side comparison on a Sig P250:

Curved Sig Rail vs. Flat 1913 Picatinny Rail

Because the tolerances on the SERPA CQC holsters are so precise (which is understandable for a retention holster that is custom fit to a specific model), the slight difference in rail geometry is enough to make the fit of the P226 MK25 not fit.

I’ll probably end up finding someone who can make a custom holster in Kydex for me. I recently picked up a Streamlight TLR-2s light for this pistol (review coming soon), and while I’m told that Safariland makes a 6280 holster for the P226R (Sig railed version) with a TLR-1 attached, I’m certain that the extra bulk from the laser assembly on the TLR-2 won’t fit in the Safariland either.

Hopefully, this short post will help others who are wondering if a Sig Sauer P226 MK25 will fit a Blackhawk SERPA holster. I love the gun, and I love the SERPA holster, but they just don’t work together.

If you’ve got a MK25 and can personally confirm a commercial holster that will fit properly, please feel free to leave it in the comments.

UPDATE: I bought the IMI Defense Holster for it that supports the Streamlight I have attached to the rail. It’s a big OWB holster, but it fits perfectly. I’ve also been able to confirm that Comp-Tac makes a shell for the MK 25, which will work with any of their holsters.