Being one of the best, or probably the best modular rifles in existence. The Sig MCX was designed to offer an utterly customizable and compact yet powerful rifle for the special forces.
While the MCX is an impeccably reliable and โcompleteโ rifle right out of the box. The modular design does find plausible reasons for adding upgrades.
Here weโll be discussing some very effective and often important upgrades to the Sig MCX to help you customize an effective, comfortable and suitable rifle.
At a Glance: Our Top Picks for Sig MCX Accessories And Upgrades
- OUR TOP PICK: Sig Sauer Romeo5 Compact 2 MOA Red Sight
- BEST BUDGET OPTION: Geissele MCX Super Charging Handle
- Sig Sauer MCX 300BLK Suppressed Complete Upper
Comparison of the Best Sig MCX Accessories and Upgrades
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Are All Sig MCX Accessories and Upgrades The Same
Absolutely not. Each Sig MCX accessory and upgrade reviewed on our list serve a different purpose. While a charging handle improves the ease of loading the weapon, a good red dot will help with quick target acquisition and low light accuracy.
The Sig MCX is itself very complete for a generic user. However, it was designed as a modular rifle for a reason. You may want to switch between calibers using a different upper. Or you may need a telescopic stock instead of the OEM folding model.
Additionally, the Sig Sauer MCX is available in a few different variants(Rattler, Virtus, SBR, Patrol, and different calibers). Where each of them has certain pros and cons to it. Plus, they may need to be upgraded for different applications.
Sig MCX (Source)
How to Choose Sig MCX Accessories
Application
Make up your mind about all the possible scenarios where youโll be using your Sig MCX. For example, a survivalist opinion would require a more compact rifle. Whereas a tactical application will need a rifle with good sights and a telescoping stock. Similarly, a competitive shooter will need a very crisp and reliable trigger.
Interchangeability
The Sig MCX is a popular weapon, but it stands nowhere near an AR-15. With that said, there are a few components between these rifles that can be used interchangeably. Additionally, try to vouch for accessories that are compatible with other weapons in your collection as well. For example, a good red dot or variable zoom scope will serve as an overall accessory for most of your weapons.
Value For Money
Try to go after a product that delivers good value for money. For example, thereโs no point spending money on a $1,500 upper if you donโt really need it. But, if you want the MCX to shoot farther and with more power, an interchangeable 300blk upper will be a good bet for you.
Review of the Best Sig MCX Accessories and Upgrades
Since Sig Sauer designed the MCX for the military, most of its internal components and upgrades are still manufactured and sold solely by them. However, the accessories are not bound by any such norms and can be found with ease.
Although, choosing the best one in a heap of the aftermarket is quite hectic. Thatโs why we scoured that enormous sea of options and came up with these best Sig MCX accessories and upgrades.
Best Overall:
Sig Sauer Romeo5 Compact 2 MOA Red Sight
Pros
Cons
What Recent Buyers Report
This red dot sight has thousands of customer reviews on online marketplaces and almost 99% of them are positive. Users like the durable and clear construction and adjustable illumination. The most appreciated feature of this sight is the motion-sensing auto/off function followed by the decent and appropriate price.
Why it Stands Out to Us
The Sig Sauer Romeo 5 is a parallax-free red dot sight with 10 illumination settings for different light conditions. It features a 50,000+ hours battery life and the motion detection feature is just amazing. The sight delivers quick target acquisition and is extremely durable to withstand the most rugged usage.
Who Will Use This Most
The sight is great for competitive shooters, tactical operations, CQB, and home defense. The red dot sight installs within seconds and provides a dependable and flawless optic solution for the MCX. The illumination setting will be useful for people with weak eyesight. Plus it improves acquisition both day and night so close-quarter hunters may also like it to some extent.
Bottom Line
The Romeo 5 is a reliable, feature-packed, and aptly priced red dot sight for a Sig Sauer MCX. It installs within seconds and offers a parallax-free view of the target with unlimited eye relief. Thus eliminating the POI vs POA issue. The scope has a very long battery life and the swing sensor on/off feature is amazing.
Runner-up:
Geissele MCX Super Charging Handle
Pros
Cons
What Recent Buyers Report
Users seem very impressed with this charging handle. The durable design and oversized charging handle are what seems to please the users most. This handle helps eliminate charging problems that arise due to scope mounts or other precarious issues.
Why it Stands Out to Us
The Geissele charging handle is the epitome of sophistication and performance for such a product. It has been meticulously designed with precise cuts and texture on all angles. The ambidextrous design is very helpful and the textured lever helps with obtaining the perfect grip.
Who Will Use This Most
The handle has been specifically designed for people who face handling issues with the OEM MCX charging handle. It is oversized and good for people with large palms. The heightened rear lip has been designed to handle the recoil of short barrel and suppressed MCX rifles which makes it even more versatile.
Bottom Line
The Geissele MCX charging handle is a useful addition to the rifle especially if you face charging issues or need a more reliable charging apparatus. The handle is very durable and ambidextrous. Plus it delivers exceptional grip for the user and will function flawlessly for years to come.
3. Sig Sauer MCX 300BLK Suppressed Complete Upper
Pros
Cons
What Recent Buyers Report
The Sig MCX 300 blk upper is a complete solution for people looking to swap calibers instantly. The upper is very well built and functions flawlessly. The suppressor is properly welded and delivers a considerable reduction in noise. Installation does require disassembly but itโs not difficult.
Why it Stands Out to Us
This upper receiver is a quick solution if you want to switch calibers. The upper comes with all necessary components and tools to make the switch. Plus the duo-trigger included in the package is way lighter than the OEM trigger. The suppressor also adds to the value of this upper.
Who Will Use This Most
This upper is suitable for people who want to use the .300 blk caliber on their existing 5.56 Sig Sauer MCX while avoiding gunsmith costs. The added suppressor makes it suitable for indoor range use and tactical applications. Plus the .300 blk is a good caliber for hunting and defense.
Bottom Line
The Sig MCX 300BLK upper is a value for money product offering instant replacement of caliber. The upper comes complete and includes an adapter and a two-stage trigger which enhances accuracy and overall performance. While the upper costs close to an MCX itself. It is a worthwhile investment for tactical operators and competitive shooters.
4. Sig Sauer MCX Curve Trigger
Pros
Cons
What Recent Buyers Report
The trigger was reported to be exceptional, precise, and easy-to-install with the Sig Sauer MCX. Users like the lightweight pull and crisp break with absolutely zero creep in the second stage. Some users mentioned the high price of this trigger but didnโt seem to mind it over its performance.
Why it Stands Out to Us
The Geissele trigger is an all-purpose and amazing trigger replacement for the heavy 7 lbs factory trigger. This trigger has a very light and crisp trigger pull with a fast and positive reset for quick follow up shots. The curved trigger helps auto-locate the finger. Plus this complete assembly is easy and quick to swap
Who Will Use This Most
The trigger is designed for both deliberate aimed fire and snap shooting. This is an all-around trigger suitable for hunting, competitions, tactical, law enforcement, and almost every application for the MCX you can think of. The crisp two-stage trigger improves accuracy and provides consistent follow-up shots.
Bottom Line
The Sig Sauer MCX has only two aftermarket options for trigger replacement. Sig Sauer and Geissele. This is a ready-to-install trigger with precision machined components having a good resistant finish. This all-purpose trigger is perfect for all applications ranging from plinking to competitions.
5. Sig Sauer MCX Caliber X-Change Kit
Pros
Cons
What Recent Buyers Report
Users appreciate the quality, fit, and finish of this caliber exchange kit. The barrel is perfectly machined and coated to prevent damage. The package includes all necessary parts and an extra bolt to eliminate any compatibility issues. The installation is very easy, but switching bolts was a matter frowned upon by some users.
Why it Stands Out to Us
The caliber x-change kit is an instant, easy, and inexpensive solution to switch between the calibers of a Sig MCX. Rather than spending a whole lot of money on a new rifle or receiver. The kit comes with all required parts and necessary instructions for installation. Plus, the durable finish and precise design is also a factor worth considering.
Who Will Use This Most
The kit is ideal for people who are looking for a viable solution to switch calibers. People who like to switch calibers for hunting, competitions, or any tactical applications will also find this kit quite helpful. The barrel is muzzle threaded and will accept suppressors or brakes to enhance the operation of the rifle.
Bottom Line
The Sig Sauer MCX caliber exchange kit is an amazing option to switch calibers without the need for buying any extra parts. This kit comes complete with all the parts and a bolt to suit the MCX. However, make sure to check with your local authorities regarding the legal implications associated with this short barrel.
6. MPX/MCX Folding Telescoping Stock
Pros
Cons
What Recent Buyers Report
Buyers report this stock to be of high quality and a flawless and reliable addition to the MCX. The folding and telescoping capability is the most impressive factor for every buyer. The easy to install/remove design and tactical functionality also grabs the attention of users. However, users with a beard reported some hair snagging issues.
Why it Stands Out to Us
The stock makes the Sig MCX evenly capable of handling almost every situation. The folding and LOP adjustable capability helps with compact storage as well as stance adjustments. The stock doesnโt require the user to perform a full disassembly which is a plus.
Who Will Use This Most
While the application of this stock is more inclined towards tactical use and compact storage. Every MCX owner interested in getting a unique and universally capable stock should consider buying this. The stock is great for people who want to save on storage space while carrying the weapon. While not compromising with LOP when shooting.
Bottom Line
The MCX stock is a fair priced upgrade for your rifle which kills two birds with one stone. Where the OEM stock can only fold, this stock can also telescope to offer better cheek weld under different shooting stances. However, the LOP adjustability is quite limited but suitable for the size of an MCX.
Advantages of Investing in Quality Sig MCX Accessories and Upgrades
Let's cover the most grounded reasons for upgrading your MCX:
Improved Performance
The upgrades and accessories reviewed above will improve the overall performance of your Sig Sauer MCX. For example, adding a good red dot sight will enhance your capabilities to quickly acquire a target in both normal and low light conditions. Similarly, adding the folding/telescoping stock will assist with performance, handling, and storage.
Versatility
As already mentioned, the Sig MCX is a modular weapon. It was designed for the special forces, which eventually means that it has to be a โjack of all tradesโ. Upgrading your MCX with appropriate accessories will make it useful for different situations.
For example, adding the Geissele two-stage trigger will make the rifle prepared for hunting as well as competitions.
Value For Money
A Sig Sauer MCX rifle costs about twice or thrice more than an average popular AR-15 model. Which means you already make a big investment when buying an MCX.
To make your investment worthwhile, it is imperative that you upgrade and accessorize your rifle to get the most out of it.
Social Factor
As a Sig Sauer MCX owner, youโll often find yourself shooting besides AR-15 owners on the range. Many people love boasting about their weapons and making comparisons. So youโd better have your MCX upgraded and accessorized to counter some brash queries. Especially when youโve already spent upwards of $2,000 on your weapon.
Conclusion
The Sig Sauer MCX is a modular weapon. Which means it was designed to be customized and complemented with accessories. Adding a few good aftermarket upgrades will improve the overall performance of the weapon while bringing it closer to your personal taste.
