Best Sig Sauer P320 Upgrades

There are a lot of contenders out there for the title of favorite modular pistol, but it's hard to argue against the Sig Sauer P320.

At its core, the P320 is a fire control unit. You can remove the FCU and combine it with a variety of different size grip modules, slides, barrels, calibers, and more. It's like Legos for grown-ups!

This modular nature has, of course, given us a massive market for upgrading and tuning this gun... which can be dizzying.

Worry not! We gathered a few of our favorite upgrades and hit the ground running.

How We Test the Best Sig Sauer P320 Upgrades

Input for this article came from the entire Pew Pew Tactical staff. Our team experience includes law enforcement, military, competition, instructing, and recreational shooting.

We’ve put thousands upon thousands of rounds through the Sig Sauer P320 in its various configurations – both factory original and heavily modified. We’ve also gotten hands-on time with upgrades for other firearms, so we have a good understanding of what you should expect when you upgrade a particular component or add an accessory.

Best Sig Sauer P320 Upgrades

1. Sig Sauer AXG Grip Modules - Best Premium Grip Module

Best Premium Grip Module

Sig Sauer P320 AXG Grip Modules

$304

at OpticsPlanet

Prices accurate at time of writing

$304 at OpticsPlanet

One of the best features of the Sig Sauer P320 is the fact the actual firearm portion is the internal chassis system, which is removable from the gun’s frame. The frame, or grip module, is not considered a firearm.

The result is you can order entirely new grip modules without the need for an FFL.

You can change the size of the gun by changing the grip module -- you can also change the entire look of your weapon.

AXG grip modules replace polymer with metal. This add weight but absorbs recoil energy better.

These grip modules come in various finishes, including the classic and scorpion.

Sadly, they are a little expensive. But boy, oh boy, they are rather sweet to have and to hold.

2. Sig Sauer X-Series Modules - Best Value Grip Module

Best Value Grip Module

Sig Sauer P320 X-Series Grip Modules

$69

at OpticsPlanet

Prices accurate at time of writing

$69 at OpticsPlanet

Sig Sauer (see price)

The X-Series Grip modules provide you with an awesome, ergonomic frame that certainly takes a step up from the standard module.

We get a more aggressive grip texture, a better beavertail, and a higher trigger guard undercut, all at a very low price.

If you've got about $50 to spend, you can make a significant upgrade to your stock P320.

3. Mirzon Enhanced Grip Module Gen 2 - Best Aftermarket Grip Module

Best Aftermarket Grip Module

Mirzon P320 Enhanced Grip Module Gen 2

$109

at Rainier Arms

Prices accurate at time of writing

$109 at Rainier Arms

Maybe you want to take advantage of the easily swappable grip modules, but you want something that goes beyond what Sig offers.

If that's the case, then this Mirzon Grip Module is for you. It differs from the OEM modules in quite a few ways.

First, the grip features finger grooves and lots of people like finger grooves.

Backing those finger grooves is a series of over-molded rubber grip panels. Those panels are quite comfortable and add a hefty degree of grip texture to the module.

We also get a massive beavertail that allows the user to establish a high, firm grip for better control.

The Mirzon is compatible with the X-Five weight to help reduce recoil, as well as an optional safety notch. It has compatibility with Gen 1 and Gen 2 takedown levers and X-Series magwells.

4. Faxon Firearms P320 Barrel - Best Barrel

Best Barrel

Faxon Firearms Sig Sauer Barrels

$133

at Faxon Firearms

Prices accurate at time of writing

$133 at Faxon Firearms

OpticsPlanet (see price)

Faxon Firearms makes some slick gear and fascinating guns. They also produce some outstanding barrels. If you are going to sink money in a better barrel, I’d buy the best.

Faxon has a bunch of different barrel options for the P320.

Of course, you have full-size and compact lengths, but also lots of finish options. This includes TiN, rainbow, and gloss black.

The barrels also fluted in what Faxon calls their flame-fluted pattern. It gives the barrel a beautiful look overall.

Want to run a suppressor or compensator? They have threaded P320 barrels too!

These barrels are rock solid, well made, and a perfect upgrade for your Sig P320; especially if you want to add a muzzle device.

5. Griffin Armament Micro Carry Comp - Best Compact Compensator

Best Compact Compensator

Griffin Armament Micro Carry Comp

$49

at OpticsPlanet

Prices accurate at time of writing

$49 at OpticsPlanet

GrabAGun (see price)

Palmetto State Armory (see price)

Compensators on competition guns might be the standard, but they can be tricky on carry guns. If you don't want to add a ton of length to your gun, then I have an option for you.

You'll still need a threaded barrel, but the Griffin Armament Micro Carry Comp keeps things small. It's hardly bigger than a thread protector but provides three mini ports to reduce recoil and muzzle climb.

It's not as effective as a full-sized comp, but you'd be surprised by how much of a difference it makes, especially on smaller pistols. I equipped the Micro Carry Comp to my P365 and CZ P-10C, and it took some sting out of both guns.

It's an affordable upgrade that's easy to carry and downright cheap.

6. Springer Precision P320 Compensator - Best Full-size Compensator

Best Full-Size Compensator

Springer Precision Open Compensator

$95

at Rainier Arms

Prices accurate at time of writing

$95 at Rainier Arms

Springer Precision produces compensators for that goofy Sig M 13.5 x 1 LH thread twist. They also provide a standard Sig Compensator for the ½ x 28 threads.

This comp has three ports that allow for a significant level of muzzle rise reduction. It’s also rated for 9mm +P and 9mm Major loads.

This compensator is pretty long and isn’t going to work great for any kind of concealed carry. It’s made for competition guns, and that’s where it is best suited.

It’s also great if you want to have fun shooting your Sig P320 fast with minimal recoil and muzzle rise.

If that's too long for you, the Shorty is a little more portable. It has a single top port and two side ports and is designed for standard 9mm ammunition. This one is better suited for a carry gun.

Springer Precision Shorty Compensator

$85

at Rainier Arms

Prices accurate at time of writing

$85 at Rainier Arms

7. Springer Precision Magazine Extensions - Best Magazine Extensions

Best Magazine Extension

Springer Precision Magazine Extensions

$35

at Springer Precision

Prices accurate at time of writing

$35 at Springer Precision

Finding extended magazines for the P320 is kind of a pain. I own a PCC that takes P320 magazines, and being stuck with 21-round magazines is a hassle. If you compete in various classes of competition shooting, you might just want a longer mag to lessen your reloading needs.

Springer Precision machines a series of magazine extensions that allow you to expand your magazine sizes at will.

I'm not just talking about +2 or +3 extensions. I'm talking magazine extensions that go up to +10 for your 17-round P320 magazines.

They also have +5 extensions and offer various extensions for 9mm, .40 S&W, and .45 ACP variants of the P320.

These magazine extensions are made from aluminum and machined to have extremely tight tolerances. Big extensions come in a range of colors.

It's one of the only options I know of that offers higher capacity without sacrificing the reliability of factory P320 magazines.

8. Agency Arms X-Series Magwell

Best P320 Magwell

Agency Arms X-Series Magwell

$96

at OpticsPlanet

Prices accurate at time of writing

$96 at OpticsPlanet

Rainier Arms (see price)

Agency is one of the original Glocksmith-style gurus who pushed the Glock platform forward. They're now working on the P320, and that's where we get the X-Series Magwell.

This magwell is purely for X-Series grip modules, which are slightly different from the standard P320 grip module.

These are concealed carry-orientated magwells that speed up those pesky reloads in the midst of a gunfight (or Instagram video) without making your pistol bulky.

9. Sig Sauer ROMEO1 Pro - Best Red Dot

Best Red Dot

Sig Sauer ROMEO1 Pro

$327

at OpticsPlanet

Prices accurate at time of writing

$327 at OpticsPlanet

Brownells (see price)

The ROMEO1 Pro is an upgraded variant of the original ROMEO1. The Pro variant packs a longer battery life, a clearer window, and a more durable design.

On top of that, we also have an optional metal shroud to keep the optic protected against the brutal world around it.

I've beaten the hell out of mine, and it works wonderfully. It’s been tossed, kicked, dipped in water, and it just keeps going.

You can choose between a 3- or 6-MOA red dot. There are 10 daylight brightness settings and two night vision settings, and the battery lasts for a claimed 20,000 hours.

10. Killer Innovations Velocity V1 - Best Slide

Best Slide

Killer Innovations Velocity V1

$454

at Rainier Arms

Prices accurate at time of writing

$454 at Rainier Arms

Decked out, cut up, optic-ready slides are all the rage these days. While they might look cool (and looking cool rules) they also serve a purpose.

Less weight means a lighter carry pistol, and less reciprocating mass means less recoil.

The Killer Innovations Velocity V1 slide does just that, trimming a little over three ounces from the slide of a compact P320. It also looks damn good.

This slide comes complete with weight-saving cuts and an entirely new grip texture.

This enhanced grip feature tosses out the idea of traditional serrations and replaces it with a positive wall you can press against as you rack your firearm.

The E.G.F. cuts are made to the front and rear of the slide. On the top, we have an RMR/DeltaPoint Pro cut for optics like the Trijicon RMR, Leupold DeltaPoint Pro, along with popular Holosun and Swampfox optics.

This specific slide will only fit compact P320s.

11. Apex P320 Trigger - Best Trigger

Best Trigger

Apex Trigger Kit, Sig P320

$62

at Brownells

Prices accurate at time of writing

$62 at Brownells

OpticsPlanet (see price)

Apex Tactical is a big name in aftermarket triggers. Currently, there are tons of companies producing aftermarket triggers, but the majority of them focus on Glock triggers.

Apex dives in deep with a wide variety of different guns, including Sig P320 triggers. Choose from flat-faced, curved, and semi-flat profiles.

Something about these triggers makes me feel like I am more in control. A more consistent trigger will help you shoot straighter and faster.

The Apex trigger systems are fantastic, and they do work with Sig's voluntary upgrades.

The Apex system is straightforward to install, and you can do it at home. It’s also an affordable option for those on a budget.

You can buy the set combined with a trigger and trigger bar, or you can purchase the parts separately.

What do you think of Apex triggers? Rate them below!

12. Bravo Concealment OWB Holster - Best Holster

Best Holster

Bravo Concealment OWB Holster

$29

at Amazon

Prices accurate at time of writing

$29 at Amazon

Choosing a holster is an important consideration. I prefer OWB, and this is my list, so deal with it. In general, the P320 is a big gun anyway, and it's excellent for OWB carry.

Bravo Concealment makes one of the most concealable OWB holsters there is. This Kydex holster is designed for close-body concealed carry.

The OWB model features a slight forward cant to increase concealment, and the belt loops can be adjusted for a high ride for more concealment.

This Bravo Concealment holster can use 1.5, or 1.75-inch belt loops and Bravo also makes a paddle system, if you prefer that. Bravo has rounded off the edges of the holster, and this allows you to carry the gun comfortably without anything being pressed into you.

The holster uses a passive retention system that locks around the trigger guard. There is a very satisfying click as the weapon is holstered. This retention also allows you to draw unimpeded without worrying about the gun falling out.

It makes concealment -- even with a larger gun -- easy.

13. Surefire X300 - Best Full-Size Light

Best Full-Size Light

SureFire X300 Ultra

$308

at Amazon

Prices accurate at time of writing

$308 at Amazon

OpticsPlanet (see price)

Midway USA (see price)

Palmetto State Armory (see price)

Show all prices

The Surefire X300 light is the gold standard for duty guns. It’s incredibly well-made, insanely bright, and built for serious duty use. I’ve seen these things get beat to hell and they still keep working.

The X300 comes in a variety of lumen counts, up to 1,000 lumens. Modes include constant on, momentary, and strobe.

The light uses a TIR lens which shoots a bright and clear light that’s concentrated for extended ranges.

It's a big light and adds some bulk to your gun. For duty or home defense, it isn’t an issue. For concealed carry, be prepared to get a holster and a good belt.

14. Streamlight TLR-7 Sub - Best Compact Light

Best Compact Light

Streamlight TLR-7 Sub

$152

at Amazon

Prices accurate at time of writing

$152 at Amazon

OpticsPlanet (see price)

Palmetto State Armory (see price)

The TLR-7 Sub is a compact weapon light that sits flush with the rail and the barrel of Glock 19-sized guns. The TLR-7 is ultra-lightweight, easy to use, and perfect for concealed carry. Toss it on a SIG P320C, and you are ready for shooting 24/7.

The TLR-7 is a 500-lumen light with a 1.5-hour runtime. It has ambidextrous on buttons that are easy to reach. The light is made from aluminum and is IPX7-rated for full submersion in one meter for 30 minutes.

How to Choose the Best Sig Sauer P320 Upgrades

Upgrading your pistol can be fun, especially when it’s as easy as swapping out parts on a Sig. It’s also expensive, though, so we recommend coming up with a plan before you start throwing money at upgrades.

What do you want to improve about your P320? If you want more personalized ergonomics, put your cash toward a grip module. Want more accuracy? Look at a trigger or barrel. If you’re chasing speed, a compensator or weight-relieved slide might do the trick. 

Once you know what your end goal is, you’ll be able to pick and choose the individual upgrades that will give you the most bang for your buck.

How to Disassemble Your Sig Sauer P320

Disassembling your P320 to install new components is easy. We made this handy instructional video for all you visual learners, so follow along!

Why You Should Trust Us

I am an NRA-certified instructor and CCW trainer out of Florida. I served as a Marine infantryman in my prior life, so I’ve had plenty of time behind guns.

Between instructing, serving in the military, and testing and evaluating firearms over the years, I’ve come to learn a thing or two about pistols and upgrades.

Final Thoughts

The Sig Sauer P320 is one of the best and most modular firearms in the world. The ability to swap calibers, frame sizes, and more makes this a fantastic little gun.

Its versatility, as well as its adoption by multiple police forces and the United States military, are going to continue to drive a massive aftermarket.

This is just a taste of what’s available now, and what will be available in the future is unpredictable.

What have you guys done to your P320s? Let us know below. Interested in learning more about these handguns? Check out our complete Sig Sauer P320 review.

Latest Update

July 12, 2024: Added more details to product selections and updated supporting content. Removed Springer Precision Magazine Wells.