Mossberg 500 Shotgun Build for Gunsite 260 Class

Brian McVickers

Administrator
Staff member
In preparation for a Shotgun 260 course at Gunsite it was time to take stock on what equipment I will be using for the class.

I've had two Mossberg 500 shotguns sitting in the safe for several years. One is a plain Mossberg 500 that came with a 28" and 18.5" barrel and a 5-round magazine. It is a post-1997 model and features a drilled and tapped receiver to accept a top rail. I use it for trap, skeet and hunting with the 28" barrel. The other is a pre-1997 500A model with a 7-round magazine, 20" barrel, but a plain receiver with no holes on top. I bought it off of a friend for a deal that was too good to pass up as he was moving out of town and could not take it with him.

For the price, it was the perfect extra shotgun to have around in the back of the truck, back of the safe or back of the closet. However, it needed a lot of help. It came to me after being "zombified"! Complete with a pistol grip, folding stock, side saddle and top saddle shell carriers, a pistol grip for the foregrip, and a cheap heat shield over the barrel. It was terribly uncomfortable to shoot, and worse to look at. I never took a picture of it but, here is something pretty close to it:
Screen Shot 2015-11-10 at 2.37.01 PM.jpg

The purchase included a set of Hougue furniture but the stock was youth size and so short that my face was up near the back edge of the receiver rather than on the stock. So, with two Mossberg 500s I disassembled both down to a pile of parts and with the help of some choice furniture and accessories from MAGPUL and Amazon Prime, I've assembled two very comfortable and reliable shotguns.

I wanted to build a gun with the following features:
- Ergonomic and adjustable stock
- Comfortable foregrip that accepts a mounted light
- A front sight
- Rear ghost ring sight
- Top rail
- A red dot reflex sight
- Sling points and a sling

A bit of browsing on the MAGPUL website and voila!
IMG_7241.jpg

After stripping down both guns I began to assemble the best parts and repurpose others.
I really wanted to combine the newer receiver, with holes for a top rail, with the larger magazine and 20" barrel but neither the 20" or the 18.5" barrels have front sights on them other than the small brass beads. The solution was either a gunsmith to solder on a front blade sites, or a clamp on front site and a rail mounted ghost ring like these I found on Amazon:
Screen Shot 2015-11-12 at 6.09.55 PM.png Screen Shot 2015-11-12 at 6.08.26 PM.png
In the past I've stayed away from the UTG brand as although it is inexpensive is is usually unimpressive quality. However, aftermarket iron sights for shotguns are surprisingly expensive and often require the additional cost of some professional gunsmithing. After some searching it appeared that all of the sites available are similar in design and materials, and the web reviews say that UTG is improving quality so I figured I would give them a try.
Ultimately I had to use the shorter 18.5" barrel and the 5-round magazine in order to accommodate the clamp on front sight. It will be two less rounds at hand but it will be a shorter and slightly more maneuverable barrel complimented by a proper set of iron sights. While researching and selecting iron sights I noticed that the traditional scatter-gun mindset about shotguns is that you don't need sights, just point and shoot. However, with modern ammunition the accuracy is much better, less scattered, and if you're going to shoot a lot of slugs then proper sights are essential. I look forward to learning more about this in the Gunsite glass.
 
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Brian McVickers

Administrator
Staff member
IMG_7586.jpg

This picture is from my first iteration, with the 7-round magazine and 20" barrel.
I laid everything out to get a sense of how it would fit together. Here is a list of everything, some items not pictured:
- The newer receiver with holes on top to accept a rail
- The MAGPUL SGA Stock
- The MAGPUL MOE M-LOK Forend
- cantilever light rail that will attach to the forend
- paraclip sling attachment point
- paraclip
- rear sling mount for the butstock
- QDM quick disconnect swivel
- MS1 sling
- UTG clamp on front sight
- UTG rail mounted ghost ring rear sight
- Mossberg 500 picatinny top rail
- Bushnell trophy red dot first strike reflex sight
- Surefire X300 Ultra light

In order to mount the MAGPUL forend I had to use the longer 7-3/4" action tube that was on the older of the two guns. The forend comes with a small locking ring and a tool to secure the nut.
Screen Shot 2015-11-12 at 7.01.31 PM.jpg Screen Shot 2015-11-12 at 7.01.44 PM.jpg
Once the forend was on it began to take shape!
Screen Shot 2015-11-12 at 7.05.03 PM.jpg

The butstock uses the same mounting screw hole as the original stock but rather than a long screw leading up from the inside of the butstock it uses a short bolt that secures through the back side of the grip. All of the hardware was included as well as several 1/2 inch spacers that can be used to customize the length of pull to the user.
Screen Shot 2015-11-12 at 7.05.51 PM.jpg Screen Shot 2015-11-12 at 9.40.34 PM.jpg
Screen Shot 2015-11-12 at 7.05.29 PM.jpg Screen Shot 2015-11-12 at 7.06.14 PM.jpg

With the forend and butstock installed it was a completely new gun.
Screen Shot 2015-11-12 at 7.27.08 PM.jpg
 

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Brian McVickers

Administrator
Staff member
Links to parts on parts list

- The newer receiver with holes on top to accept a rail
- The MAGPUL SGA Stock - link
- The MAGPUL MOE M-LOK Forend - link
- cantilever light rail that will attach to the forend - link
- paraclip sling attachment point - Forward link
- paraclip - link
- rear sling mount for the butstock - llink
- QDM quick disconnect swivel - link
- MS1 sling - link
- UTG clamp on front sight - link
- UTG rail mounted ghost ring rear sight - link
- Mossberg 500 picatinny top rail - link
- Bushnell trophy red dot first strike reflex sight - link
- Surefire X300 Ultra light - link
 

Ray_G

Explorer
Great write up, will be interested to see how it shakes out for the course-and if you like the light in that configuration. I've never liked lights on shotguns unless they were the surefire foreends.
r-
Ray
 

robert

Expedition Leader
Nice. I ended up sending out my short barrels to be threaded for choke tubes after being disappointed by the patterns. You're right, modern shotgun loads will group a lot tighter these days and a good barrel makes a difference.

Eta- two other things you might want to look into are an oversized safety or at least the metal version that comes on the 590, and a new follower. There are a couple of slicker mag tube followers out there.
 
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screwball48

Explorer
In the never ending battle of price vs quality it is very hard to pass up on Magpul. The SGA line of accessories is very well put together. Your shotgun is looking good. Let us know how well it performs in the class.
 

Brian McVickers

Administrator
Staff member
Overcome your fear of gunsmithing. Send it to Hans at Vangcomp.


Not a fear of gunsmiths. In fact, I have had Hans and his team to some work on one of my rifles, talk about a nice guy, Hans is great!

For this gun, leading into a class, I did not think that it needed or justified a $400 Vang Comped barrel or even a bunch of silver solder work.
However after the class and learning more, which I will cover in another thread, I plan on getting a good front target sight soldered on.
The clamp on site worked ok but the issue is that the little adjustable sight post would rotate and adjust itself slightly up and down. It stayed on target but was not perfect.

Regards,
Brian
 

Brian McVickers

Administrator
Staff member
Great write up, will be interested to see how it shakes out for the course-and if you like the light in that configuration. I've never liked lights on shotguns unless they were the surefire foreends.
r-
Ray

Hi Ray_G
After a solid 1,500 rounds with this setup and about 300 of them at night with both handheld and weapon mounted lights, I will be reworking the light solution.

At Gunsight, our first night drill was using a handheld light. Then we moved to weapon mounted lights and on the first shot I understood why the instructor had snickered at seeing my light setup earlier. After the first shot I yelled out "Ow!" and the instructor just started laughing and then said "did that surefire light bite your finger?!"

Sure enough the pointy pressure switch on the 300 Ultra pushes back and digs into your thumb bad upon recoil. The answer for that particular light is a remote mounted pressure switch.

Regards,
Brian
 

Brian McVickers

Administrator
Staff member
In the never ending battle of price vs quality it is very hard to pass up on Magpul. The SGA line of accessories is very well put together. Your shotgun is looking good. Let us know how well it performs in the class.

Agreed on the Magpul! The gun ran great and has continued to since the class. 1,500 rounds so far and no issues.

I found a nice addition by taking Magpul forend grip intended for an AR and mounting it to the shotgun. It allows for a nice finger hold for indoor carry and it gives a larger surface to put pressure on when firing for a quick cycling of the action as soon as it breaks loose.

I will post pictures soon
 

Ray_G

Explorer
Hi Ray_G
After a solid 1,500 rounds with this setup and about 300 of them at night with both handheld and weapon mounted lights, I will be reworking the light solution.

At Gunsight, our first night drill was using a handheld light. Then we moved to weapon mounted lights and on the first shot I understood why the instructor had snickered at seeing my light setup earlier. After the first shot I yelled out "Ow!" and the instructor just started laughing and then said "did that surefire light bite your finger?!"

Sure enough the pointy pressure switch on the 300 Ultra pushes back and digs into your thumb bad upon recoil. The answer for that particular light is a remote mounted pressure switch.

Regards,
Brian

Brian-
Makes sense, and truth be told I'm not surprised...thumb bite is a lot better than the scope bite scar I have that is barely visible on my right eyebrow when I let an M40A1 get a little loose doing rapid fire. In retrospect its all good training.

I've never been very happy with the tape switches for the long haul but they do work ok; if/when I do another 870 I think I'll do the foreend. Thanks for the class write up, jealous of the trigger time!
r-
Ray
 

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