I had several posts about Mossberg 500/590 and was surprised by number of questions about this shotgun. First of all, I recommend checking infographic: Differences Between Remington 870 vs Mossberg 500 shotguns. It explains differences in controls and design. Mossberg 500/590 is a great and very popular shotgun. There are 10,000,000 of Mossberg 500/590 shotguns made to date.

So, this post is about the best and must have upgrades for Mossberg 500/590 shotguns.

Mossberg

Mossberg

There are many upgrades and accessories for this shotgun. You can upgrade almost any part of the Mossberg shotgun. And that is great because you can customize it to fit your needs. Hunters need longer barrel and sling, law enforcement officers need short barrel, sidesaddle and flashlight. Mossberg 500/590 cab be used successfully for any purpose: hunting, home defense, tactical use, survival etc.

So, let’s start with the best inexpensive but must have upgrades: safety button and follower.

Oversized safety button for Mossberg 500/590

Standard Mossberg 500/590 safety is made of plastic and has low profile. Aftermarket oversized safeties have larger profile for more reliable work. They are made of sturdier aluminum or steel. You can disengage oversized safety faster and easier. Unlike factory safety, it is easy to disengage oversized one even when wearing gloves.

There are two of the most popular oversized safety buttons available for Mossberg 500/590: Brownells and Vang Comp Systems.

Vang Comp Systems Oversized Safety for Mossberg 500/590

Vang Comp Systems Oversized Safety for Mossberg 500/590

Vang Comp Systems Oversized Safety for Mossberg 500/590

VCS is a company that is well know for quality upgrades and accessories for firearms. Vang Comp Systems Mossberg 500/590 oversized safety is CNC machined of billet aircraft-grade aluminum. It is sturdy, it is rock-solid. Mil-spec hard coat anodize to withstand hard use.

Oversized safety enables shooter to manipulate shotgun even under stress when fine motor skills don’t work. Vang Comp Systems Mossberg 500/590 safety is taller and wider than factory safety button. It is much more comfortable to use. Your thumb will never miss this button. Install oversized safety for faster and more reliable disengagement.

Installation is easy. Hex head screw, stainless steel lock washer and hex wrench included.

The price is about $30

Recommended Product:
Vang Comp Systems Oversized Safety for Mossberg 500/590

Vang Comp Systems Oversized Safety for Mossberg 500/590

Vang Comp Systems Oversized Safety for Mossberg 500/590 on Brownells

Brownells Oversized Safety for Mossberg 500/590

Brownells makes a lof of high-quality firearms upgrades and accessories. And Brownells Oversized Safety for Mossberg 500/590 is no exception. Safety is made of steel which makes it simply indestructible. It is heat-treated for extra hardness and wear resistance, with a durable, matte, black oxide finish.

Mossberg 500/590 Oversized Safety from Brownells

Mossberg 500/590 Oversized Safety from Brownells

Oversized safety has a raised, crisply grooved ridge for easy operation. Your thumb will have more surface for faster disengagement. Steps in the body of the safety are cut deeper than factory part for additional grab even with wet hands or when wearing gloves.

The unique feature of this oversized safety is reversible design that allows shooters with small or medium-size hands to position the thumb ridge farther back to help them operate the safety without having to break their grip; shooters with large hands can place the ridge forward to give them more room.

Recommended Product:
Mossberg 500/590 Oversized Safety from Brownells

Mossberg 500/590 Oversized Safety from Brownells

Get Oversized Safety for Mossberg 500/590 on Brownells

Aftermarket follower for Mossberg 500/590

S&J Hardware Mossberg 500/590 Follower

S&J Hardware Mossberg 500/590 Follower

I don’t like Rem 870 factory follower and recommend to replace it with one of the aftermarket Remington 870 magazine followers.

But standard Mossberg 500/590 is made of metal and works properly for thousands of rounds. You can replace it if you want to change color or try magazine follower made of different material: Mossberg 500/599 Magazine Follower on Brownells.

Sidesaddle (Received Mount Shell Carrier) for Mossberg 500/590

Sidesaddle is one of the most popular accessories for shotguns. It is very nice additional to any scattergun. Receiver mount shell carrier enables you to have from 4 to 8 rounds on your Mossberg 500/590. It is important to have additional ammo because magazine of shotgun holds only 4-8 rounds.

If you store your Mossberg 500/590 shotguns unloaded then sidesaddle is a must have upgrade! When you grab your shotgun in the night, you have only ammo that is in the shotgun and on the shotgun. Sidesaddle enables you to have 4-8 rounds on a shotgun and don’t search for ammo under stress.

Many police officers have sidesaddles installed on their shotguns. Usually, they have different types of ammo in a receiver mounted shell carrier. It is good to have both slugs and buckshot in sidesaddle. That way, you can be flexible and choose ammunition you need at the moment.

It is very easy to use a sidesaddle. You just need to train to load ammo from a sidesaddle several times and you will see how easy it is. It is comfortable to load both chamber and magazine tube from sidesaddle.

Installation of the sidesaddle is very simple and doesn’t require modifications of your Mossberg 500/590

There are several companies that manufacture sidesaddles for the Mossberg 500/590 shotgun: Mesa Tactical, TacStar.

Mesa Tactical Sureshell Holder for Mossberg 500/590

Mesa Tactical offers by far the most options for tactical or home defense Mossberg 500/590 shotguns. Mesa Tactical Sureshell sidesaddle is the most expensive but the most reliable one. It is made of aluminum which is very difficult to damage. Other companies offer plastic sidesaddles which are cheaper but not as reliable as aluminum.

Mossberg Mesa Tactical Side Saddle

Mossberg Mesa Tactical Side Saddle

On the inside of the shot shell holder there is an elastomer tube made of Santoprene thermoplastic. This elastomer helps to keep the shot shells snug while inserted in the shell carrier. All of the Mesa Tactical sidesaddles for Mossberg 500/590 are sold with a back up white elastomer tube that can be swapped out by unscrewing the screws found in the back plate of the sidesaddle. All Mesa Tactical sidesaddles also come with an adhesive backed rubber gasket, this gasket will help prevent the sidesaddle from making surface contact with the receiver. The gasket acts as a protective layer between the back of the sidesaddle and the surface of the shotguns receiver thus protecting the Mossberg 500/590 shotguns finish and preserving its market value.

Mesa Tactical Sureshell Holder for Mossberg 500/590 SPECS:
6065 T6 Aluminum
Weight- 3.6-4.2oz
Stainless steel fasteners and Chicago screws
Satoprene Elastomer tubing installed in black and a back up in white
Adhesive backed rubber gasket
Shells held in place under satoprene elastomer thermoplastic tension
Hard anodized matte back coating
Mesa Tactical 4 shell Suresaddle: MSRP: $65.00
Mesa Tactical 6 shell Suresaddle: MSRP: $70.00
Mesa Tactical 8 shell Suresaddle: MSRP: $85.00

Recommended Products
Mesa Tactical Sureshell Holder for Mossberg 500/590

Mesa Tactical Sureshell Holder for Mossberg 500/590

Get Mesa Tactical Sureshell Holder for Mossberg 500/590 on Brownells

TacStar Shell Holder for Mossberg 500/590

TacStar has been known as an inexpensive alternative to some of the more expensive sidesaddles currently on the market for a variety of shotgun platforms. They manufacture sidesaddle for Mossberg 500/590. It is inexpensive and many shooters use this model without any problems.

The Mossberg 500/590 TacStar sidesaddle is comprised of 2 pieces, the aluminum sidesaddle receiver mounting plate and a nylon plastic 6 round shot shell holder mounted to the shotguns receiver using two large Allen screws. The nylon plastic shot shell holder is held into place on the aluminum mounting plate with 6 flat head Allen screws.

Mossberg 590 TacStar Sidesaddle

Mossberg 590 TacStar Sidesaddle

One of the problems with the Mossberg 500/590 TacStar sidesaddle is that a few of the 6 flat head Allen screws would come loose due to the recoil of the shotgun. Because of the open design, once the small flat head Allen screws start coming loose they will fall off into the dirt, grass and so on and the shooter will most likely never see them again. Applying a bit of Loctite to all of the screws might help prevent this from happening.

The second problem you can have over time the two large sidesaddle mounting screws (that screw in through the receiver and into the aluminum mounting plate) had actually ripped the threading out of the mounting plate. Upon inspection, the only hypothesis I could come up with was that once again the recoil and frequent use had something to do with it. I called TacStar and had them send me another mounting plate and screws free of charge. My customer service experience with TacStar was exceptional. Not everyone will experience the same issues but since I’m a fairly avid shooter I will assume I’m not the only one who has experienced similar malfunctions with the TacStar 6 round sidesaddle.

Several of the readers of the Rem870.com blog also had similar problem with sidesaddle mounting screws.

This sidesaddle is recommended for a budget build and people who don’t anticipate shooting frequently. As there are many people who don’t mind looking past the design flaws for the justifiability of the low price.

TacStar Shell Holder for Mossberg 500/590 Specs:
Weight: 5.3oz
1 Nylon black plastic shell holder
1 Matte black (type of finish unknown) aluminum mounting plate
Made in the USA
Shell holder works with shell tension
TacStar 6 round sidesaddle MSRP: $34.99
Price seen as low as $24.50

Recommended Products
GetTacStar Shell Holder for Mossberg 500/590 on Brownells

Get TacStar Shell Holder for Mossberg 500/590 on Brownells

Get TacStar Shell Holder for Mossberg 500/590 on Brownells

Magazine Extension for Mossberg 500/590

Mossberg 500/590 shotguns often hold up to five rounds of ammunition, but when you add the extension you should be able to hold up to ten rounds. The people who use magazine extensions are usually those who practice at a shooting range or want to use shotgun for home defense. It is for people who want to shoot at a target closer to them while firing multiple consecutive rounds. Police and members of law enforcement commonly have these extensions on their department issued shotguns. That way they don’t have to worry about running out of ammunition too quickly when they are shooting at suspects or enduring a tough situation where they wouldn’t have too much time to reload. As for homeowners looking to protect their families, it is your choice as to whether or not you feel that an extension is necessary. Usually you will be shooting close range at an intruder, but it is to possible a target under stress. So it is better to have additional ammo in your shotgun.

There are several popular magazine extension for Mossberg 500/590:
Nordic Components
Vang Comp Systems
Choate

Magazine Extension for Mossberg 500/590

Magazine Extension for Mossberg 500/590

Nordic Components Magazine Extension for Mossberg 500/590

Magazine extension tube is one of the first upgrades shotgun owners usually buy and install. This is understandable because shotguns have very limited number of rounds. There are a lot of different magazine extensions available on the market. You can get magazine extension separately or complete magazine tube extension kit.

Nordic Components Magazine Extension for Mossberg 500/590 is one of the best ones. It is made of aluminium. It consists of 3 parts (tube, tube cap, tube nut). This extension comes with high-quality spring with black coating. And the best thing – a lot of shooters use these extensions and have no problems with them.

Now let’s have a closer look at all advantages Nordic Components extension gives to a shooter…

This extension is lightweight. If you compare it to other ones you will see a great difference in weight. IT is nice to have such lightweight extension for better balance.

It consists of 3 parts: tube, tube end cap, tube nut. This allows you to have one +5 tube for competitions and one +3 tube for home-defense. +5 tube allows to have more rounds but it sticks out too much, it is much better to have a shorter tube for use in close quarters.

Also, after installation, you can take out the end cap and look inside your magazine tube to check if everything is ok.

This is one of the best magazine springs. It will fit any magazine extension you can find.

Updated Modular eXtension Tube incorporates new features designed to eliminate common problems with shotgun magazine extensions. The MXT features a reinforced magazine tube end-cap, which prevents end-cap damage from high recoil and impact. A new clamp relief groove eliminates clamp slip during recoil, which can damage the finish of the firearm and change the point of impact. MXTs feature the same threads on either end of the tube, allowing the user to flip it, changing the location of the clamp groove.

Bundle:
Extension (consists of 3 parts)
Spring

The price of this magazine extension tube is about $80.

Recommended Product:

Nordic Magazine Extension for Remington 870

Nordic Magazine Extension for Remington 870

Get Nordic Magazine Extension for Mossberg 500/590 on Brownells

Vang Comp Systems +1 Round Magazine Extension for Mossberg 500/590

Short, screw-on magazine extensions add one or two additional rounds to tactical and sporting shotguns without increasing overall gun length. Replaces factory magazine cap with no permanent modifications. Machined from solid steel bar stock for a much stronger system to resist dents. Included sling loop can be installed for left- or right-handed shooters. Includes a smooth feeding stainless steel follower for enhanced reliability.

Vang Comp Systems +1 Round Magazine Extension for Mossberg 500/590

Vang Comp Systems +1 Round Magazine Extension for Mossberg 500/590

Recommended Products
Vang Comp Systems +1 Round Magazine Extension for Mossberg 500/590

Vang Comp Systems +1 Round Magazine Extension for Mossberg 500/590

Get Vang Comp Systems +1 or +2 Round Magazine Extension for Mossberg 500/590 on Brownells

Mossberg 500 High Capacity Shotgun Kit

Mossberg 500 doesn’t allow you to simply install extension because of the construstion of the barrel. That is why you have to buy a new barrel and magazine extension to converts your field gun to a tactical home defense shotgun.

Mossberg 500 High Capacity Shotgun Kit

Mossberg 500 High Capacity Shotgun Kit

High quality, OEM components allow you to easily transform your Mossberg 500 into a reliable, high-capacity, self defense weapon. 20″ long barrel chambered for 2¾” and 3″ magnum 12 gauge loads features a fixed cylinder choke for maximum pattern coverage at combat ranges. Plain brass bead front sight for fast easy sight acquisition. Magazine extension threads solidly into the receiver to provide 8-rounds of firepower; knurled takedown screw retains the tube in the magazine support on the barrel to eliminate the need for a separate barrel clamp. Includes extended-length magazine spring for reliable feeding.

Recommended Products
Mossberg 500 High Capacity Shotgun Kit

Mossberg 500 High Capacity Shotgun Kit

Get Mossberg 500 High Capacity Shotgun Kit on Brownells

Best Flashlight for Mossberg 500/590

CDM Gear MOD-C Light Clamp

CDM Gear MOD-C Light Clamp

CDM Gear MOD-C clamp is one of the best available on the market. It enables you to have any 1 inch tactical flashlight on your shotgun. No movement under recoil, no scratches because 3M polyuerathane pads were attached to the clamp. Such pads are included and not only protect finish but also eliminate any movement.

Some people don’t know but you can attach quick detach swivels on the other side of the CDM Gear MOD-C clamp. This feature is very handy when you need to attach a sling.

CDM Gear MOD-C Flashlight holder is not only holds your flashlight reliably but also works as a barrel and magazine clamp. So it has lots of features which you receive in a low profile, light weight, compact and reliable piece of equipment.

I recommend getting ne of the following flashlights to use together with CDM Gear MOD-C clamp:
FAB Defense Speedlight
Surefire G2X
Streamlight Polytac

Fits Mossberg 500 7 shot, 590 (not the 590A1 or SPX models, see MTC clamp)

Recommended Products:

Surefire LED WeaponLight forend for Mossberg 500/590

One of the best flashlight for the Mossberg 500 shotgun is the Surefire Forend Light. This is one of the more expensive flashlights but it is also one of the best and most reliable on the market. It is a compact light that integrated to the forend of your shotgun rather than to the side of the shotgun. Some shooters like their light coming from the bottom of their shotgun because it makes the shining light align with the front sight that helps you aim. The Surefire Forend Light retails for roughly $225, but some are more depending on the amount of accessories that come with it. Either way, adding any kind of light source to your Mossberg 500 shotgun will be beneficial to you in the long run.

Surefire Forend with Integrated Flashlight

Surefire Forend with Integrated Flashlight

Surefire LED WeaponLight forend for Mossberg 500/590 features:

200 Lumens of Output for 2 Hours
Virtually indestructible LED and TIR lens produce brilliant beam optimized for close- to medium range applications
Switches—Momentary-on pressure pad, constant-on rocker, system-disable rocker
Construction—High-strength aerospace aluminum with Mil-Spec anodizing; impact-resistant polymer; coated, tempered window
Includes high-energy 123A batteries with 10-year shelf life

Stock and Forend for Mossberg 500/590

There are a lot of stocks you can choose and it would take a lot of time to describe them all. Let’s talk about the most popular stock:

Magpul Stock and Forend for Mossberg 500/590

The SGA is an adaptable stock for the Mossberg 500/590/590A1 12 gauge shotguns, designed with a wide range of customizable features and accessories to meet individual end-user needs. You can adjust Length of Pull, add cheekriser, sling apapters etc.

Magpul Stock and Forend for Mossberg 500/590

Magpul Stock and Forend for Mossberg 500/590

The M-LOK Forend is a simple, lightweight forend for 500/590/590A1 12 gauge shotguns with 7-5/8″ action tube assemblies, designed to provide much-needed adaptability with the attachment of optional M-LOK accessories and mounts.

NOTE: The Mossberg forend in the sets will NOT fit the Mossberg 500 with 6-1/2″ action tube assembly or the Maverick or current production Mossberg 500 synthetic with pinned-in action tube assembly without replacing with the 7-5/8″ action tube assembly.

Recommended Products
Magpul Stock and Forend for Mossberg 500/590 Magpul Stock and Forend for Mossberg 500/590

Eotech XPS Holographic Sight on Mossberg 590 Shotgun

Eotech XPS Holographic Sight on Mossberg 590 Shotgun

Eotech XPS Holographic Sight on Mossberg 590 Shotgun

Holographic or Red Dot sights are good for new shooters or shotgunners which don’t have enough time for training. They are simple and allow very quick target aquisition. The can even help experienced shotgun owners especially when shooting slugs on a longer distances.

Eotech makes a lot of holographics sights. This version is named XPS, it is much smaller, it is lightweight and I really like it.

Here is photo where you can see how compact Eotech XPS is:

Eotech XPS Holographic Sight on Mossberg 590 Shotgun

Eotech XPS Holographic Sight on Mossberg 590 Shotgun

Eotech XPS is reliable, adjustable and has lots of features. And the best thing that it is lightweight.
The only disadvantage is a high price but holographic sights are all priced high.

Broken Mossberg 500/590 Firing Pin Washer and Elevator Assembly

Here are two of the recent problems which happened to Mossberg 500/590 of fellow shooters.

Broken Mossberg 500/590 Firing Pin Washer

Broken Mossberg 500/590 Firing Pin Washer

Broken Mossberg 500/590 Firing Pin Washer

This small part is called Mossberg 500/590 Firing Pin Washer. It blocked the action completely and only gunsmith was able to disassemble a shotgun.

Recommended Product:
Mossberg 500/590 Firing Pin Washer

Mossberg 500/590 Firing Pin Washer

Get Mossberg 500/590 Firing Pin Washer on Brownells

Broken Mossberg 500/590 Elevator Assembly

Broken Mossberg 500/590 Elevator Assembly

Broken Mossberg 500/590 Elevator Assembly

That happened on several shotguns, so it looks like factory defect. That breakage is surprising because such part as Elevator Assembly is one of the main parts of the trigger group and should be difficult to breake.

Recommended Product:
Mossberg 500/590 Elevator Assembly

Mossberg 500/590 Elevator Assembly

Get Mossberg 500/590 Elevator Assembly on Brownells

Read also: Infographic: Remington 870 vs Mossberg 500