Gun Review: SIG SAUER P365-FUSE 9mm Pistol

Sep 30, 2024

Today’s feature is from our companion service SHOOTING NEWS WEEKLY.

When SIG SAUER introduced the P365 at the 2019 SHOT Show, it caused a minor explosion in the concealed carry pistol market. Cramming 10+1 rounds of parabellum into a form factor that other makers had only managed to fit seven rounds appealed to the ever-growing market for concealed carry pistols.

Almost as interesting was the P365’s modularity. Like SIG’s P320, the P365 is built around a serialized fire control group that constitutes the legal “gun.” That means you can buy all of the other components — grip modules, slides, barrels — to mix and match and create your own customized version built around the central FCG.

It didn’t take SIG long to start expanding the P365 universe with more and larger models. The pistol that was famous for its small, concealable size added ever bigger models to fit a huge range of hand sizes, use cases, and individual preferences. From the P365X, P365-XL, to the XMACRO, XMACRO COMP and the metal-framed AXG Legion, the line has mushroomed in features and physical size. Now, with the addition of the P365-FUSE, it seems the 365 ecosystem is now complete.

Well maybe. We don’t pretend to know what the minds in New Hampshire may still have planned for the P365 line, but the P365-FUSE may be the ultimate expression of what a P365 platform pistol can be.

SIG calls the full-size P365-FUSE the fusion of capability and concealment in its marketing materials and that’s not just a bunch of hot air. This is a 4.3-inch barreled pistol that holds a full 17+1 rounds of 9mm ammo. It comes with one flush-fit 17-round magazine and not one, but two 21-round extended mags.

SIG has fitted out the FUSE with an LXG laser-engraved grip module that has aggressive, but very comfortable texturing and is ergonomically fantastic. The flat-faced nickel-plated trigger is easily one of the best striker-fired triggers we’ve ever had the pleasure of pulling. There’s also a removable magazine well and excellent, not-quite suppressor height sights.

SIG SAUER P365-FUSE with a SIG FOXTROT2R weapon light.
 
Under that 4.3-inch barrel (for reference, that’s only .2 inches shorter than, say, a GLOCK 17 or a .4 inches less than a P320-M17), is a three-slot rail with plenty of room for a full-size weapon light like the FOXTROT2R pictured above. The slide has excellent, grippy serrations and texturing ensuring you’ll get a good grip on things no matter where you choose to grab it.
 

The sights on the P365-FUSE are excellent. SIG went with more of a competition style fiber optic front sight and a black serrated rear. If you don’t like the green front sight, the FUSE also comes with yellow and red tubes, too. The sights aren’t quite suppressor height, but they’re close.

Those high(er) sights make for an ideal co-witness sight picture in the lower third of the window. Here you see it through SIG’s new ROMEO-X Enclosed Compact red dot sight.

As for overall size, here’s the P365-FUSE back-to-back with a SIG P320 compact.

And here’s where SIG has done a little more of their physics-defying magic. As you can see above, while the P365-FUSE has a longer slide, it seems to be the same height as the P320-COMPACT. But that’s not quite true. The P320-COMPACT is 5.25 inches in height while the P365-fuse is slightly shorter at 5.1 inches. Yet the FUSE carries two more rounds than the P-320 COMPACT.

Probably the biggest difference between the two platforms, however, is in their width. The P320-COMPACT is 1.25 inches wide. The P365-FUSE is 1.1 inches. That probably doesn’t sound like much but it makes a significant difference in how well a gun carries.

I tote the P320 a lot in colder months when more clothing is appropriate. It’s comfortable and concealable and lets me carry 15+1 rounds around. But the P365-FUSE is about to bump the 320 from my rotation. The FUSE’s longer slide doesn’t negatively affect ease of carry or concealment. So, the thinner, higher capacity FUSE is going to be my carry gun of choice when capacity is key.

SIG ships the P365-FUSE with that removable mag well -- which I promptly removed. That’s easily done with the turn of a single screw. Then I subbed out the medium backstrap for the smaller one, the better to fit my unusually small hand. I’m not really sure why the small and large backstraps don’t have the same texture pattern as the medium strap and the grip frame, but whatever. They feel the same with a satisfying grippiness.

As you’d expect, the P365-FUSE slide is optic-ready. The slide is milled in the nearly-ubiquitous RMSc compact mount, so you’ll find no shortage of good red and green dot optics that will mount without having to result to awkward adapter plates.

As you’ll see in the video above, Jeremy and I racked our brains for something about the P365-FUSE we don’t like. We simply couldn’t come up with anything. It’s a full-size, full capacity 9mm pistol that’s slimmer and easier to carry than almost anything else its size. It has a great trigger and feels fantastic in the hand.

The other plus to the FUSE is the P365 platform’s modularity. The P365-FUSE would make a great first gun. Besides everything it already does well, it’s also an entree into the P365 universe of options. Pick up a shorter slide, barrel and a smaller grip module — all of which you can have shipped right to your door — and you have yourself an ultra-compact gun that will conceal incredibly well no matter what you’re wearing or what time of year it is.

Specifications: SIG SAUER P365-FUSE

Caliber: 9mm
Capacity: 17+1 (1x17rd, 2x21rd magazines)
Barrel Length: 4.3 inches
Overall Length: 7.2 inches
Width: 1.1 inch
Height: 5.1 inches
Weight: 21.1 ounces
Optic Mount: RMSc
Price: $799

— Dan Zimmerman