Best Sig MPX Upgrades & Accessories (Complete List)

The goal with this Sig MPX was to put together the best upgrades and accessories available on the market.

To build the ultimate sub-gun or pistol caliber firearm that can be used for home defense, truck/vehicle gun, or something just to have fun at the range with.

The Sig MPX is truly an impressive firearm and there was a lot of excitement when everyone heard the news that Sig Sauer was making this gun. It came out in 2015 and I was lucky enough to pick one up.

What is a sig MPX?

The Sig MPX is very unique being a short-stroke push-rod gas system.

The Gen 2 version is the one I have and it is a 9mm 8 inch barrel variant that came with the SBX Brace (side folding pistol brace). It is an excellent platform for this class of firearms.

The Gen 2 version is nice because it is modular and can swap barrels to change calibers to 9mm, 357sig, and 40 S&W. It also comes with a keymod rail system.

Sig Sauer has actually stopped making the Gen 2 / 8 inch variant of the MPX, but these upgrades & accessories will work across the board on all of the new sub-models they are currently offering.

Below I list all of the Upgrades & Accessories I added to the firearm and the reasoning behind why they work well on the MPX.

Also, at the end of this post, I mention what I still want to add.

Sig Sauer’s Current Models In Production

• Click Here to view them on Sig’s website
• Click Here to download the owner’s manual

Sig MPX Stock

So technically this would become an SBR (short barrel rifle) if I added a stock. Unfortunately, I’m not allowed to own SBRs in my state so I cannot add a stock but there are a lot of Pistol Braces that are totally legal for me to use and that’s what I ended up doing.

This is an easier route and I think most people will add a brace and not a stock due to the headache that comes with the process.

Sig SBX folding arm brace

The SBX Brace is actually pretty comfortable to shoulder when firing the MPX but it looks god awful on the gun. (Everyone knows looking cool is the most important thing).

These Braces have been discontinued but I am happy I still have the brace because nowadays they are hard to come by and have gone up significantly in value.

Sig PSB collapsable arm brace

The PSB brace which is made by SB Tactical was the first upgrade I did to the MPX.

I liked the overall look of the new brace and the functionality of it and I have to admit it looks absolutely awesome on the gun.

This allows for a 3 position adjustment by pressing a button on the top part of the brace. It is very quick and easy to operate and again it really adds to the overall look.

Note: This Brace will also work on the Sig MCX

Click Here to check out the current prices of the PSB brace.

Sig MPX Sights

This is one negative I’m going to add about this firearm. Also, this might just be my experience but when I purchased my MPX it did not come with any fixed sights.

This was a little frustrating because I think Sig Sauer could have added a set with the gun (this could have been a mistake on their end).

Magpul MBUS pop up sights

I ended up throwing on some Magpul MBUS pop up sights because I had an extra set leftover from a previous rifle build.

These are good sights and get the job done in case my optic goes down for any reason.

They are relatively common and can be picked up at just about any local gun store and I see these included with most rifles.

They are pretty standard but I think they are just a little overpriced.

Click Here to check the current prices of the Magpul MBUS Sights

Sig MPX Pistol Grip

The grip that came on the MPX is actually pretty good. It’s the standard Sig style pistol grip that I see comes on most Sig rifles. I have a personal preference when it comes to pistol grips.

Magpul MOE K2+

I happen to like the Magpul MOE K2+ pistol grip. I put this on every AR-style rifle I have and did the same when it came to the MPX.

It is very comfortable and has a slightly rubberized texture to it and it does a great job keeping your hand where it belongs on the firearm.

There is a small storage compartment in the grip that can be used to store any small items you wish. Perfect for having some extra batteries for your optic or weapon light.

Magpul offers a few different color options too which is cool. They are also fairly priced. This was a quick and easy upgrade for the Sig MPX.

Click Here for the current prices of the Magpul MOE K2+

Sig MPX Red dot optic

There were 2 options when it came to adding an optic on the MPX. I had to factor in price and budget but didn’t want to lose any quality and reliability.

EOTech XPS2-OPMOD

Originally when working on this build I wanted to go with an EOTech XPS2 Holographic sight in FDE (Flat Dark Earth).

I wanted this optic specifically because I haven’t got around to purchasing one yet and I think it would be perfect for the Sig MPX.

I specifically like the OPMOD variation of this optic because it has a green reticle instead of a red.

This is supposed to help your eye pick up the reticle quicker on very bright days or when looking into direct sunlight.

The OPMOD also has better waterproofing and has more brightness settings compared to the original.

Because of the high price of them and any quality optic for that matter I still haven’t gotten around to getting an EOTech……yet! I will soon though.

Click Here for the current prices of an EOTech XPS2 OPMOD

Trijicon MRO

I already had a Trijicon MRO and that is what I put on the MPX. I’m a big fan of the MRO and like how the objective lens is larger, this allows me to pick up the red dot very quickly.

Trijicon is also a solid brand that has been in the game a while and I am confident in the reliability.

Click Here for the current prices of a Trijicon MRO

I mounted it on the MPX using the Geissele Super Precision Mount and it is probably the best mount available for this optic. It is very good and holding zero and built like a tank.

I highly recommend this mount.

The battery life is also very good. When the optic is left on a medium brightness setting, it will last for 5 years which is impressive. (I still replace the battery every year though).

Click Here for the current prices of the Geissele Super Precision Mount

Note: Once I get an EOTech XPS2 I will add it to the Sig MPX and put the Trijicon MRO on an AR-15 (that’s the plan anyway)

Weapon Light

Every firearm that intends to be used for self-defense needs a good weapon light. You need to be able to identify your target so a weapon light is a must-have upgrade.

I added the Streamlight ProTac HL light and mounted it using the Magpul Light Mount. This isn’t the cleanest setup and I don’t have a pressure switch but this is a much more affordable option and gets the job done.

I am a big fan of the ProTack HL and own a few of them. They are very bright and have decent battery life on high output. They have three modes: High, Strobe, and Low.

Click Here for current prices of the Streamlight ProTac HL

There are better mounting options for this light, I recommend something that attaches directly to the key mod rail. I had the Magpul light mount laying around so that’s what I went with for now.

Click Here for current prices of the Magpul Light Mount

Eventually, I would like to add a Surefire Scout light with a pressure switch and a Cloud Defense LCS. This is what I have set up on one of my AR-15s and it awesome but it is a little expensive.

Angled Foregrip

Many gun laws don’t make much sense and the vertical foregrip one on a “pistol” is one of them. So because the Sig MPX is a pistol and not an SBR you cannot add a vertical foregrip.

An angled foregrip is perfectly legal though.

I added the Seekins Precision K20 KeyMod Angled Forward Grip. It has a low profile look to it and it is very slim.

It mounts directly to KeyMod so there is no need to add additional rail sections. It also has a QD sling swivel mount integrated which is a nice added feature.

Click Here for current prices of the Seekins Precision K20 Angled Foregrip

Note: I ended up removing the angled foregrip because it took up too much rail space and realized it was uncomfortable while shooting. I put the small hand stop back on that came with the Sig MPX

More Magazines

The MPX only came with one 30rd magazine and this just isn’t enough. I ordered 2 more magazines and of course, Sig has to charge a lot of money for them.

I had to make sure that I got the Gen 2 magazines (the ones with the brown/FDE followers). 

The early magazines had issues and the Gen 2 ones work well. I believe they are made by Lancer and are reliable. I just wish they weren’t so damn expensive.

Click Here for the current prices of the Gen 2 30rd Mags

Related Articles

• Remington 870 Tactical – Upgrades
• Best Sig MCX Upgrades & Accessories (Complete List)

sig mpx upgrades & accessories still needing

Here are some accessories and upgrades that are still going to be added to the MPX eventually. (Gun parts are expensive so I cant get everything all at once)

Sling Mounts

If you prefer having a sling point sling setup you do have to add anything to the Sig MPX. In the back of the receiver, there is a slot to add a QD Sling Swivel mount.

Even if you use a 2 point sling you can still use this slot as an attachment point at the rear of the firearm and you just need to add an attachment point somewhere near the front of the MPX.

There are a lot of options when adding a front slot to attach a QD Sling Swivel and it can be placed anywhere on the Key-Mod rail system.

Click Here for the current prices of a QD Sling Swivel Mount

Since I added the angled foregrip underneath the rail, it has a QD Sling mount integrated into the angled foregrip.

This was a quick and easy way for me to add my 2 point sling. Even though I like attaching it a little further forward this gets the job done.

Ferro concepts Slingster

I currently like running a 2 point sling and this is what I recommend on almost everything. Being that the Sig MPX is a smaller firearm with only an 8-inch barrel, a single point sling would work well also.

I personally like the Slingster by Ferro Concepts and that is my go-to sling. It has a quick pull tab for easy adjustment too. However, any good sling would work.

Click Here for the current price of the Ferro Slingster Sling

Geissele Super MPX SSA Trigger

Geissele makes a great trigger and I have shot some of theirs in some rifles. They are very consistent and have a clean break. The only downside of them is the price.

After some research on the Geissele Super MPX SSA Trigger, I know this will be added to the Sig MPX. They are a favorite company of mine and everything they make is top-notch.

Again this is another upgrade that I am holding off on until I have some extra money to spend or they go on sale.

Click Here for the current price of the Geissele Super MPX SSA Trigger

Radian Raptor LT Charging Handle

All Raptor Charging Handles are ambidextrous which is good for any left-hand shooters. Even if you are not left-handed they are a nice little upgrade to the Sig MPX.

I have one on a rifle and it works great and is very good quality. It adds to the overall aesthetic of the MPX as well.

Click Here for the current price of the Radian Raptor LT Charging Handle

Surefire M600DF

Originally I thought about getting the newer Surefire M300C because it is smaller and I figured it would fit better on the 8 inch Sig MPX.

After looking it up and doing some research I discovered they were roughly the same price as the Surefire M600DF.

The Surefire M600DF is bigger and brighter and I didn’t want to pay the same price for a lower-powered weapon light. I already have one too and like everything about it.

When comparing the size of it up next to the Sig I will attach it on the right side of the rail and it will fit perfectly and not be too large.

Click Here for the current price of the Surefire M600DF 

Surefire Pressure Switch

Having the option to activate the white light without having to break your forward grip is an advantage and adding a Pressure Switch is how you can achieve this.

It will give you the ability to activate your weapon light momentarily and not have to keep switching from constant on.

Surefire makes a good pressure switch to accommodate their lights and I like the one that still leaves the constant “on button” in the back of the light as well.

Click Here for the current price of the Surefire Pressure Switch

Cloud Defensive LCS Mount

Once you have the light mounted where you like it and have the pressure switch running off the back with the short cable you need a way to secure the switch to the rail.

I have seen people use zip ties and electrical tape but this doesn’t look very clean.

The Cloud Defensive LCS Mount provides a great way to secure the pressure switch to the rail.

Underneath the small mount, there are channels from the excess wire to route through and this is the proper way to run your pressure switch.

Click Here for the current price of the Cloud Defensive LCS Mount

Best In-class

The Sig MPX is truly an amazing firearm and I believe it outperforms everything else similar to it. Now it is one of my favorite firearms and is a pleasure to shoot.

All of the upgrades and accessories that have been added, compliment the gun nicely and make it close to a do-all firearm.

Sometimes I have regretted a little while after purchasing a new gun because I later see something that is better. With the MPX that is definitely not the case.

Again I am happy I have the Gen 2 version with the 8-inch rail. It is the best version of this gun and if you disagree let me know why in the comments down below.

Sig Sauer really needs to bring this variant back into production!

What is the first upgrade you are going to do to your MPX and what one do you like the most? Let me know in the comments.

Complete List of Items Mentioned

(Click the links for the most up to date prices)

• SBX Brace (discontinued)
• PSB Brace
• Magpul MBUS Sights
• Magpul MOE K2+ Grip
• EOTech XPS2 OPMOD
• Trijicon MRO
• Geissele Super Precision Mount
• Seekins Precision K20 Angled Foregrip
• Streamlight ProTac HL
• Magpul Light Mount
• 30rd Extra Magazines 
• QD Sling Swivel Mount
• Ferro Slingster Sling
• Geissele Super MPX SSA Trigger
• Radian Raptor LT Charging Handle
• Surefire M300C
• Surefire M600DF 
• Surefire Pressure Switch
• Cloud Defensive LCS Mount