Back in my Tips & Tricks number 11 video, I promised that more videos on 870 magazines
were on the way.
Unfortunately, life got kind of busy after that, and a lot of the magazine-related topics
that I’d like to cover are waiting on testing or research that I haven’t had time to really get into.
However, some folks have commented asking how to take an 870 from an extended magazine setup
to a standard capacity for hunting or sporting,
or maybe just a lighter and simpler non-extended fighting configuration.
This may seem pretty straightforward - just remove the extension
and install a magazine cap, right?
Well, that’s the gist of it, but there are some complications that can pop up, and plenty
of little details that one should be aware of.
This topic - or aspects of it - also comes up fairly often on the forums I frequent,
so there’s plenty of meat here to fill a tips & tricks video,
and I’m already really familiar with the ins & outs of the topic.
So, let’s get started.
I’ll be switching from this fairly typical 18.5 inch fighting build
- with an S&J Hardware single-piece extension -
to a non-extended hunting setup with this vent-rib Rem Choke barrel;
but what I’ll cover will apply to other configurations as well.
Note that this is a normal 12ga 870 with an extension added to the standard 4-round base magazine tube.
If you have one of the newer Tactical models with the nonstandard single-piece 6-round mag tube,
sorry, you’re stuck with that capacity.
These special 870s really need their own video; for now I’ll just say that you don’t want
to buy one of these if you’re after a multi-role shotgun.
Anyway, step one in the process is to get your extension off.
Ensure that the gun is unloaded, then remove anything that’s clamped to the extension,
followed by the extension itself.
Pull out the spring, and also take off the barrel if you’re changing it.
You can refer to my take-down video for more detailed instructions, but if you can take
apart your 870 for cleaning, you should already know how to do everything I’ll be showing in this video.
Now let’s talk about the parts you’ll need. First up is the magazine spring.
While you can cram a long extension spring under a magazine cap, it’ll usually be way
too long for the application, and that can lead to function problems.
If you’re switching down to a 4+1 capacity, you really ought to use a more appropriate spring.
Now, if your gun started out as a standard-capacity setup to which you added a mag extension,
you may still have the original spring.
But if you lost it, or your gun came with an extension installed, you’ll need to get a new one.
If you’re removing a mag extension, you’re most likely dealing with a 12ga 870, and Remington
offers three springs to choose from for these.
The first is the standard 4-round 17-7 stainless spring.
It’s a good spring for hunting, sporting, or home defense.
It’s what I use, and what I usually recommend.
The second is the longer Police spring used in 4+1 Police and military 870s.
The extra length provides a bit more force than the standard 4-round spring, and it should
last longer in heavy-use applications.
There are a couple negative trade-offs though, so I would more recommend this one for duty weapons
or range rental guns that really see a lot of rounds between spring replacements.
The final option is a special nickel-plated version of the longer Police spring.
It’s meant for 4-round Marine Magnums, and offers better corrosion resistance than plain
17-7 in especially harsh conditions, but it’s more expensive.
I could go into a lot more detail about the trade-offs of these springs and which to use for what application,
but I’ll stay on topic for now, and spin that off into a future video.
If you’re taking an extension off something other than a 12ga, these springs should also
work for 16ga and early large-frame 20ga 870s.
For newer small-frame 20ga guns, the 4-round spring you’ll want to get is part number F400452.
There are also a number of aftermarket spring options, but they can be picky about followers
or other parts, and often require the customer to cut them to the proper length.
That’s a whole separate can of bees that I don’t want to open right now.
If you know what you’re doing and want to go aftermarket, that’s up to you,
but my default recommendation is to stick with factory springs in a standard-capacity magazine.
They’re inexpensive, fit spring retainers properly, work reliably with virtually all
factory & aftermarket followers, and are sized specifically for this tube length.
Now for the follower.
If you were running some fancy aftermarket follower in your magazine extension, you can
generally keep using that for a non-extended configuration if you like.
Pretty much any half-decent follower will function reliably in a seamless 4-round tube
with a factory spring.
There are a couple things to be aware of, though.
Some aftermarket cup-style followers have holes that allow you to feel when the magazine is empty.
It’s a nice safety feature, but sometimes these holes are big enough for magazine plugs to pass through.
This can damage shotshells or cause malfunctions, so be sure to check for this, and switch to
a different plug or follower if necessary.
Followers with tails take up more tube space than cup-style followers.
If you’re using a magazine plug, you can simply cut the plug down to compensate,
but if you want to use the whole tube, a solid-bodied follower with a tail will almost always be
less space-efficient than a cup-style follower when using factory or factory-style springs.
However, depending on the specific follower & shells you’re using, you may find that
you can still get the desired number of rounds into the magazine without changing the follower.
Next up is the spring retainer.
Spring retainers are optional parts, but they have several benefits for a sporting 870,
especially if you switch barrels frequently.
If your shotgun had a magazine extension installed, then it doesn’t have the dimples that new-style
plastic spring retainers lock into, so the only option is a press-in retainer.
The factory metal spring retainers honestly aren’t very good.
If you have a 12ga 870, I would strongly recommend using a Benelli retainer instead.
See this video for details.
If you don’t want to use a spring retainer, you don’t have to.
But if your magazine cap has these teeth inside, I would recommend placing a factory magazine follower
over the forward end of the spring to avoid snags.
See my first tips & tricks video for info on that.
Speaking of magazine caps, let’s get into that.
A key point that is often overlooked is that 870 caps should have some way to lock down
against the barrel, or they’ll tend to back off under recoil.
I’ll cover cap retention systems in more detail in a future video,
but here’s what you need to know right now.
If the barrel you’re going to be using has a spring-loaded detent staked into the guide ring,
what you want is a magazine cap that has dimples or ridges on its underside.
These will engage the detent and help keep the cap in place.
If you’re using a barrel that doesn’t have this detent,
or the magazine cap you want to use has a flat bottom and can’t engage a detent,
you’ll want to get ahold of one of these:
This is a wave-style lockwasher sized to fit around the magazine tube of 12ga 870s.
When compressed flat between the barrel guide ring and a magazine cap or extension,
this provides resistance that helps keep things from coming loose.
I’ve seen a few sources for these washers, but the ones I use are sold by Wilson Combat.
If you do need to buy a magazine cap, you have plenty of choices.
There’re basic caps, caps with simple sling swivels, more complex sling plates & push-button QDs,
or caps with witty graphics.
There are also specialized caps that incorporate weights, lights, or lasers;
and I even know of one cap that serves as a quick-connect bipod adapter.
If you just need a functional cap and you’re already ordering other parts from Remington,
you could keep things simple and go with a factory cap.
Otherwise, check your local stores or online for something that has your desired features
and/or finish.
I would recommend avoiding caps with the internal-ratchet teeth, as they serve no purpose
without a plastic spring retainer, and they might snag the spring.
Also, be sure to look for a dimpled or slotted rim if your barrel has a detent.
If you’re trying to pinch pennies, used caps tend to be roughly half the price of new ones.
So, once you have all the parts you need, just put them together.
Insert the follower, then the spring, magazine plug if you’re using one, retainer if desired,
wave washer if needed, then tighten the magazine cap firmly against the barrel guide ring.
Thanks for watching, hope it helped.
I’m sorry it’s been quiet here for awhile, but this channel is - and will remain -
an ongoing project, even if I have to take extended breaks sometimes.
So, please don’t be shy if you have feedback or topic ideas,
and if you have questions, go ahead and ask them.
Even when I’m not actively working on videos, I keep an eye on things here
and read every comment and message that I get.
Until next time - which hopefully won’t take as long - please continue to defend our
second-amendment rights, and promote the shooting sports as the safe, enjoyable, and beneficial hobby it is.