It is not uncommon to find self defense shotguns modified to use a magazine extension. You would be hard pressed to find a tactical shotgun that didn't have an extended magazine. The mag extension allows the user to add one or more shells (above the factory count) to the weapon's magazine tube. How many can be added depends entirely on the length of the magazine extension. How long should your extension be? Most folks prefer the extension to not extend past the end of the barrel so limiting the extension to that length is probably the right answer for you.
A number of companies manufacture magazine extensions. After spending some research time in a few shotgun forums, Nordic Components was a name that coming up with good things said about it. Their magazine extension for the Benelli SuperNova was almost twice the price compared to others but having a quality extension on a quality shotgun seemed like a good thing to do. So, I decided to try the Nordic magazine extension on my SuperNova.
I did some on-line pricing and found a local shop, Cactus Tactical, here in the Phoenix area that carried the Nordic line. I stopped by on a Saturday morning and had a nice chat with the man (owner?) behind the counter. He had a Nordic 2 shot extension on the shelf and after discussing some other things (lighting, barrel clamps, etc.), I headed for home after having done a quick test fit in the store (yes, I had my SuperNova with me).
The installation of the magazine extension is pretty easy. Your first
step is to put a pair of safety glasses on as you will be working with springs
and parts that are under tension. There is no reason in the world why you
should not protect your eyes!
With your safety glasses on, start by unscrewing the cap from the end of the magazine tube. Be careful....there should be a spring retainer in the end of the tube (visible when the cap is removed) unless someone removed it before you got in there, and if so, the cap will be under spring tension so be careful, just in case.
Next, remove the spring retainer using a pair of needle nose
pliers or better yet, a pair of snap ring pliers. This retainer will be
under tension so be careful. You won't be using it when the Nordic
extension is installed.
This is the Nordic 2 shot extension for the Benelli SuperNova. It is made from three parts (more on that later). As you can see, it is just long enough to accommodate two more shells (these are 2 3/4" shells).
You will reuse the shell follower (red cap that you can see at the end of the magazine tube when there are no shells in it) that is attached to the factory spring. Just pull it off the end of the old spring and put it on the new spring when you install it. I put the factory spring, spring retainer, and the tube cap in a ziplock bag and put it with the other gun parts.
The Nordic extension came with a 45" long replacement spring (lower
spring in above photo). It
appears that they use the same spring for all of their extensions (one size fits
all after it is trimmed). The supplied directions suggest you trim the
spring to be approximately 10" to 16" longer than the entire length of the
magazine tube. I removed the end of the Nordic extension, screwed the
extension onto the magazine tube threads, and with the new spring inserted into
the tube, I measure 16" past the end of the tube. I cut off the excess
spring with a wire cutter and tossed the piece into the trash. Note:
After a couple of tries, I ended up cutting another 4" off of the spring, which
put mine right at 12" past the extension.
Time to reassemble. I screwed the end cap back onto the
extension (previously removed for measuring the spring length) and removed the extension from the magazine tube. After making
certain the follower was on the end of the spring, the spring was carefully
compressed into the magazine tube until I could slip the Nordic extension over
the end of the spring and thread the extension onto the magazine tube.
Make sure you still have those safety glasses on!
I mentioned earlier that the extension came in three pieces. To change to a longer or shorter extension, all you have to do is change the tube. The end cap and coupling sleeve are reused. I noticed that Midway USA has the tubes listed on their web site at less than half the price of a complete magazine extension.
That's it! You have now installed (what may arguably be) the best magazine extension according to many on the shotgun forums.
I tried it out at the range today and ran a couple boxes of
shells (bird shot, slugs, and buckshot) through the
Benelli SuperNova. It
worked as expected with no feeding issues or other problems. I like the
look and better yet, the results.
The Benelli has been to the range twice now with the Nordic
extension in use. I'm happy to report that I've had no problems with it
(it stayed tight and showed no signs of not loosening). It has seen duty
with slugs, buckshot, and birdshot and reliably fed all of them.
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