The Best Mossberg 500 and 590 Upgrades

Confession time: I love shotguns. 

There is just something about delivering what’s best described as a “payload of lead” with each pull of the trigger. 

Plus, the shotgun just so happens to be the most versatile weapon in my armory.

With a single 12-gauge pump gun, I can hunt deer, birds, and bears. I can defend my home or shoot skeet.

A shotgun is a do-it-all kind of weapon, as long as it’s at close range. 

One of my favorite modern pump-action shotguns comes from the Mossberg 500 series — the Mossberg 590. The Mossberg 500 series and I go back a long, long way.

Over the years, I’ve swapped some things out on my trust 590, upgrading it here and there.

And I’m here to share some of my favorite accessories and parts so you too can take your Mossberg to the next level.

So let’s get started.

Best Mossberg 500 Upgrades

1. Knoxx Breachersgrip Gen III

In most cases pistol grip only shotguns suck. They are painful to shoot, difficult to control, and fill very niche roles.

Very few work well…but the Knoxx Breachersgrip Gen III from Blackhawk Industries is the exception. 

The Knoxx Breachersgrip works with the 590, 500, and Mossberg Shockwave. 

The Shockwave is an odd gun legally.

I won’t dive into the details, but it must remain over 26 inches to be a non-NFA item. This traditionally means you have to use the included Shockwave Raptor grip. 

I made a big bet when I got the Blackhawk Knoxx Breachersgrip Gen III. (To my ATF agents and forum lawyers I just attached a Mossberg 18.5 inch barrel I had on the gun before installing the grip. I don’t even joke about NFA violations.)

The Breachersgrip is a recoil-reducing pistol grip designed for short shotguns used in breaching operations. It greatly reduces felt recoil and makes PGO shotguns comfortable. 

I have put some nasty rounds through guns with this grip, including powerful PDX buck and ball slugs. I felt almost nothing.

It turned a 12-gauge powerhouse into something closer to a .45 ACP from a 1911. 

Recoil reduction is important for more than keeping your wrists from aching. With this grip, I can confidently aim the shotgun and shoot faster and more efficiently with it. 

The Breachersgrip is great for replacing standard Mossberg JIC pistol grips, or those found on cruiser models. Most importantly the Breachersgrip from Knoxx and Blackhawk is one way to tame the Shockwave. 

Check out more of our favorite grips (including recoil-reducing ones) in Best Mossberg 500/590 Stocks.

2. Magpul MOE Shotgun Forend

Magpul SGA furniture is fantastic for shotguns, and like most Magpul gear it’s extremely high quality and modular.

The Magpul SGA Mossberg 500/590 MOE Pump allows you to add stuff only where you need it. 

You can attach M-LOK or MOE accessories directly to the pump or attach rails to accommodate any accessory that mounts to Picatinny rails. This allows the easy mounting of lights, lasers, and even chainsaw grips. 

The pump doesn’t overlap the receiver so it doesn’t interfere with side saddles if you want one. Also, it looks cool as hell. 

To mount it to a short-barreled shotgun or firearm you have two options.

Option 1 is to Dremel the pump to fit the short action tube. It’s easy but takes a bit of time and the necessary tools. 

Option 2 is an adapter from Hogue. This makes the Magpul MOE Shotgun pump compatible with shorter action tubes. 

And don’t forget some M-LOK Rails to mount your favorite accessories. 

3. Magpul M-LOK Vertical Grip

If rock a Magpul forend, a Magpul M-LOK Vertical Grip is the perfect addition.

Why? Because with a vert grip you are a lot less likely to short stroke the shotgun. 

You get a really solid grip and a stable platform.

To effectively mitigate recoil, the best method is the push-pull — pushing forward with the firing hand and pulling rearward with the pump hand.

It’s a lot easier to pull on a vertical grip without worrying about your hand slipping.

Since the M-LOK grip mounts directly to the Magpul pump it’s not going to slide off the pump either.

On Mossberg 500/590s with pistol grips, a vert grip adds a lot of control to the gun. It makes it easier to aim, and helps prevent getting an eye full of shotgun.

What do you think of Magpul’s products? Rate them below!

4. XS Big Dot Front Sight

Night sights can make a big difference in low-light shooting performance. If you’re like me and still rely on the boomstick for home defense you want to see your sights.

The XS Big Dot front sight is a combination day and night sight that replaces your teeny tiny bead. It’s a massive, high visibility front sight that’s easy to see regardless of the time of day. 

This sight stands high enough to co-witness with my chosen optic and optic rail. 

At night it glows bright and you’ll have no issue getting that rock-solid front sight focus.

The XS Big Dot is a must-have even if you rock an optic.

5. Ergo Tactical Stock Adapter

The Mossberg 500’s aftermarket is quite large, but it’s nowhere near as large as the AR-15’s.

Some of the best stocks and pistol grips I’ve ever used came from ARs, and the ability to adapt them to my favorite pump shotgun was a godsend. 

The Ergo Stock Adapter is just that.

This small, affordable part allows me to easily add my chosen AR-15 pistol grip, buffer tube, and stock to my Mossberg 500 and 590.

It attaches in about a minute, giving you instant access to a multitude of system options, including the ability to add a brace to a Mossberg Shockwave.

It’s also affordable, which is always nice. 

6. Blue Force Gear Vickers Sling

When it comes to sling selection for any weapon, I’m pretty damned biased. I like my Vickers Blue Force Gear slings.

I own a standard-issue, an AK limited edition, a Vickers One sling, and even one of the rare Vickers Medic slings. 

The two-point Vicker Tactical sling from Blue Force Gear is my all-time favorite. What makes it interesting is the rapid adjustment tab. A quick pull rearward or forward of this tab tightens and loosens the sling. 

This allows it to be tightened down when climbing, crawling, or running and then bam, instantly loosened for shooting and maneuvering.

The quick adjustment tab allows for easy adjustment and control over your weapon. 

While traditionally found on a carbine, there’s nothing stopping it from being an excellent Mossberg 500 sling.

7. Opsol Mini Clip

The Opsol Mini Clip is one of the coolest little gadgets you can add to a Mossberg 500 series shotgun. 

It’s a drop-in, drop-out upgrade that allows you to reliably use those Aguila mini shells. 

Those mini shells don’t always run super reliably in shotguns, but this adapter makes them run like a dream in the Mossberg 500. In a standard 5-shot tube, you can load nine rounds of the Aguila mini shells. 

This is the best $15 I’ve ever spent on a shotgun — especially for those shooting Mossberg Shockwaves. 

8. Hornady RAPiD Safe Shotgun Safe

Okay, so this isn’t an upgrade, but the Hornady RAPiD Safe is my personal choice for securing my self-defense shotgun.

You have three different options for opening this safe. The first is your traditional key and lock option, which is great in case the power goes out and batteries die. 

The second method is through a four or six-digit combination.

The third is my favorite…the RFID keys. These look like little round chips but come outfitted with adhesive to mount to almost anything.

There is also an included wristband that has a built-in RFID chip. So, you can wear the wristband while sleeping and if something goes bump in the night you have the key ready. 

Though cool, it does offer limited security to your gun, and shouldn’t be used for long-term storage. 

One other downside is you can’t mount an optic and store your shotgun. While the trigger is exposed, the design of the safe makes it so the weapon must be stored with the action opened.

This means it’s nice and safe. 

Check out more of our favorite safes for long guns and pistols in Best Gun Safes.

9. Aridus Industries CROM

If you are running and gunning with a Mossberg 500/590 series shotgun with a set of ghost ring iron sights, I’ll point you to the Aridus Industries CROM mount.

CROM stands for Co-witness Ready Optic Mount. This replaces your rear ghost ring and makes mounting an optic easy.

The CROM utilizes a Trijicon RMR footprint, so you can Trijicon optics or a great many alternatives that have settled on the Trijicon footprint.

Behind the optic sits a ghost ring or, by choice, a Rob Haught style open rear sight. Either way, you can mount a co-witness applicable sight with a set of iron sights.

It’s a great minimalist mount and perfect for those with ghost ring sights and lets you get a rock-solid cheek weld before pulling the trigger.

10. KE Arms Optic Mount

Oh, you don’t have ghost rings…but you have a bead front sight? AND you want a low-profile optics mount?

Well, I gotcha covered, guys and gals. The KE Arms Optic Mount is a cheaper option that eliminates the inclusion of a built-in rear sight.

The KE Arms Optic mount keeps things super low and simple.

It bolts onto your pre-tapped Mossberg receiver and provides several different patterns for mounting a variety of optics — including the Aimpoint Micro series, Trijicon RMR, and the Deltapoint.

It’s a simple solution to a problem that eliminates the need for and the height of a Picatinny rail.

11. Tactaload Flash 5 Stock

Stashing extra ammo on your gun is a must, and one new way is the Flash 5.

The Flash 5 is a Mossberg stock with a built-in magazine storage option that allows you to store five rounds of 12-gauge that range in size from 2.75 inches to 3.5 inches.

Its storage setup is essentially a magazine with a spring, follower, and spring-loaded nob to keep your shotgun shells in the stock.

Pull the shell from the stock, and the spring-loaded nub retracts and allows you to draw a shell for a quick reload. The Flash 5 offers numerous advantages over the standard side-saddle.

• Ambidextrous design
• Faster tube reloads
• Shells are entirely secure and protected from the elements.

As a stock, it’s also great and gives you an adjustable length-of-pull similar to the Magpul SGA stock.

It’s super comfy, and provides a great cheek weld, and is tough as nails.

12. Streamlight TL Racker

Mounting a light to a pump-action shotgun isn’t easy.

A manual action makes arranging lights, pressure switches, and more difficult. However, Streamlight provides an affordable, bright, and capable option for shotgunners.

The TL Racker replaces your pump with a system that integrates a light into the design.

Two ambidextrous buttons make using it easy, and it provides 1,000 lumens of light with the press of a button.

Its bright white light makes it easy to identify a threat and tosses a blinding white light into the eyes of a threat.

13. Holosun 507C

I think the little Holosun 507C might be the best shotgun optic on the market.

Why? Well, it packs a multi-reticle system that utilizes three different reticles.

One includes a 32 MOA circle, and that circle is the very best for shotguns. With the right load, you can pattern your load to that circle at certain ranges.

I use the 507C with my Federal FliteControl load, and I’ve patterned it at 5, 10, and 15 yards.

I know that within those ranges, no pellets will escape from the 32 MOA circle.

This ensures I have total accountability of my buckshot pellets and know exactly where the shot will land. It’s quite handy for precision-oriented shots.

Conclusion

The Mossberg 500 platform is well-proven, dependable, and as evidenced above, almost endlessly upgradeable.

You can tune and customize a Mossberg 500 almost as much as you can an AR-15. So what are you waiting for? Build the Mossberg of your dreams!

These are my favorite upgrades, but I want to know yours. For more general upgrades like lights…check out our Best Home Defense Shotgun Upgrades.