compact all-purpose tactical shotgun (cats)

COMPACT
ALL-PURPOSE
TACTICAL SHOTGUN (CATS)
BY J.M. RAMOS
With stock folded, the 14 inch barrel CATS has the same
overall length of an AR-15 PDW with 7.5 inch barrel. Both
guns are dressed in Mission First Tactical furniture.
It’s been a number of years since
I did a two-part series article on this
famous fighting shotgun for SAR magazine. Since then much more sophisticated product enhancements for
shotguns became available and the
time has come to epitomize the Model M870 one more time. In addition to
all these exciting developments, there
are also several interesting high capacity bullpup pump action shotguns that
have come along in the likes of the KelTec KSG and the Turkish powerhouse
UTS-15. These two guns are virtually
the same in concept having twin tubular magazines on each side of the barrel and loads in the same manner and
packs an awesome 15-shot firepower.
Indeed, these distant bullpup twins
have very impressive credentials. The
question is, are these contenders go-
The CATS shotgun with the Fab Defence
GL-stock folded and sling removed.
ing to be around for a long time or are
they simply a fad of overnight sensation
and gone tomorrow? On the contrary,
the Model 870 has been around for decades and has been battle proven by
the U.S. military and police forces the
world over. To date, the M870 still remains as the main bread and butter of
its producer – Remington Arms. With
the resurgence of military style firearms
in the 21st century, many new accessories for this gun have been develop
and produced to upgrade its vintage
image to the more modern tactical
format. Much of the improvements
given in particular are attention to furniture style and rail systems. Older
models such as the Remington M1100
semi-auto have somewhat milder recoil than its pump action sibling but not
good enough to inspire me to shoot
more than two dozen rounds continuously without a thick shoulder pad or
taking a long pause. The introduction
of pistol grip and straight stock configuration for these guns made a difference
in recoil management most particularly
in muzzle control. There are also bolton mounting kits that are tailored to
accommodate AR-15 M4 style stocks
and pistol grips. These adapters are
available in hi-impact polymer or aluminium material. Other manufacturers
went further and explored the idea of
incorporating a telescoping hydraulic
energy built into an M4 style stock extension (Enidine) or a dual spring-loaded recoil reduction system built into the
pistol grip (SpecOps). The SpecOps
appears to have the most recoil compensating effect dedicated to reducing
shotgun recoil. However, this kit lacks
the aesthetics and clean lines – something most buyers would go for.
Among these specialty stocks
that featured a built-in recoil absorbing
system, it was the Fab Defence patented GL-shock absorbing stock that
tops them all in both ergonomics and
aesthetics. This Israeli made stock
featured a premium silicone chrome
alloy spring to power its built-in stateof-the-art recoil reduction device. Another unique and patented feature not
found on any AR type stock is its builtin anti-rattle mechanism in the form of
inward tabs that squeezes both sides
of the stock extension’s lower section
creating a very snug fit when using a
commercial tube. Although the manufacturer claims that the stock will fit both
Mil-Spec and commercial tube, the GL
will have some looseness with Mil-Spec
tubing due to its smaller diameter. Just
like most modern M4 style stocks today,
the GL also features watertight battery
storage and integrated QD sling connectors on both sides. Priced at just
under $100, the GL stock is one of the
best bargains around with excellent
quality and good looks to go along. It
comes in a variety of tactical colors and
available with optional cheek piece. I
have tested the GL stock quite extensively with varieties of 2 3/4 and 3 inch
Magnum (00 buck shots and slugs) and
the felt recoil is definitely tamed down.
It’s like shooting a mild 20 gauge with
a 3 inch Magnum and even milder with
2 3/4 inch shell. The usual hard kick
of the butt during recoil is replaced by
a “push” like feel and it’s not harsh or
painful by any means. The recoil absorbing system on this stock really
works and will definitely find a good use
with any big bore AR or AK. The introduction of these recoil absorbing stocks
for use with powerful full bore service
rifles and shotgun truly benefited the
average consumer without having to go
through the services of a gunsmith for
expensive barrel porting or installation
of a muzzle brake device that may require machining and brazing.
Ideally, to create the ultimate
Compact All-purpose Tactical Shotgun
(CATS) you must start with a medium
size M870 – preferably a police model
with a 14 inch barrel and carefully outfit
it with the right components. This barrel length puts the overall length of the
weapon to the legal 26 inches with the
stock folded. My ideal compact all- purpose tactical shotgun must be accurate
up to 50 yards with slugs and up to 2530 yards with 00 buckshot. It should
have a minimum 5 plus 1 capacity for
defensive application and can accommodate tactical accoutrements such as
folding stock (for low profile transport),
pistol grips, optic, light or laser, BUIS
sight and bipod for those accurate 50
yards shot in certain situations. With
all things considered, this tactical package can also be an ideal duty gun for
patrol officers who prefer the portability
of a folder for ease of carry or transport. In designing the CATS shotgun,
the main emphasis is focused on controllability, accuracy, portability, ease
of operation, ergonomics, weight and
aesthetics. While it does sound like
this is going to be quite an undertaking, in reality it is not, simply because
most of the ingredients you are going
to need is now readily available in the
market. It’s just a matter of selecting
the right components and putting them
together properly.
For recoil management, my top
pick of accessory would be the Fab
Defence GL and the trend setting Mission First Tactical Battle-Link Minimalist
Stock (BMS). The MFT BMS overall design feature is quite impressive. I predict that superlight collapsible stocks (to
match the new style slim-line forearms)
will be the next wave in tactical stock innovation and MFT’s Minimalist is there
first and definitely the one to beat. This
stock does not have the usual built-in
compartment to accommodate spare
batteries or tools to allow trimming
as much materials as possible, which
helps to keep the weight down to bare
minimum. The way I look at it, most
pistol grips and forward grips have the
internal storage for this purpose anyway so the Minimalist will do just fine
without this feature. This stock is made
of specially developed reinforced, super tough polyamide from Du-Pont’s
military plastic division that is amazingly light at less than 6 ounces. This
kept the CATS shotgun weight down
considerably when you take into consideration other conventional polymer
stocks can easily weigh ten times or
more in comparison. Another excellent
feature of the Minimalist is the fit to the
stock extension. It is very snug with absolutely no rattle or play once installed.
The secret is the stock’s assembly hole.
This portion of the stock is not round
as with conventional stocks; rather it
has four corners. If you look closely
inside the stock you will see that the
assembly hole has a two- step section.
The opening of the stock is correct for
the diameter of the tubing being used
(available for Mil-Spec or commercial).
As you push the stock in, the tubing will
encounter a resistance once it hits the
second step of the hole, which is intentionally made undersize. As you force
the stock further into the tubing, the four
corners of the hole will flex and tightens
against the tubing on all corners resulting in a very snug and rattle free fitting.
Once the stock is fully assembled to the
stock extension, it slides smoothly from
one index to another without the usual
rattle or looseness normally associated with other conventional collapsible
stocks. What a clever idea. It really
works without the need for a fancy lever
that may not always do the job. The
engineers at MFT really did their homework on this one. To keep the Minimalist ultra light, the overall pattern of the
stock is highly skeletonized with the
lower half of the butt being extensively trimmed down but leaving the cheek
piece section with just the perfect width
for maximum comfort when shooting.
Another remarkable feature of the stock
is the angled section of the butt plate.
At first glance, one might think it’s just
to make it look more fancy or different
from other stocks with flat plates. However, once you shoulder the weapon,
you will instantly discover it’s not for
decoration. The angled section of the
butt acts as a fulcrum that works in natural harmony with the operator from low
ready position to instant target acquisition in one precise fluid motion. None
of the other competing stocks has this
unique feature. The Minimalist stock
makes the CATS shotgun lighter, more
balance and handles more like a tactical short barrelled .308 rifle than a
scattergun. This is one formidable CAT
to reckon with.
The installation of a butt stock and
pistol grip to the M870 will require an
adapter. There are several brands of
adapter for this shotgun currently available in the market. They are made of
polymer or aluminium materials. Of
these adapters, I choose the Command Arms (CAA) RS-870 aluminium
pistol grip/stock adapter. This adapter
is CNC machined from aircraft grade
aluminium and superbly finished and
anodized. One thing I like about the
CAA adapter is it offers a true straight
stock configuration and not with a
slight heel drop like others that allows
the original factory sight to be utilized.
A straight stock arrangement like the
AR-15 not only provides better control
and recoil management to the weapon
but it also assures comfortable aiming
posture with tall back-up sights. The
CAA adapter will take the AK47 pistol grip and AR-15 butt stock (fixed or
collapsible). There are two AK pistol
grips that I found perfectly suited for the
CATS shotgun: namely the Magpul AK47 MOE grip and Mission First Tactical
Engage AK-47 pistol grip (EPG-47).
These two grips differed slightly in configurations with Magpul featuring the
more traditional slab-sided styling of a
1911 pistol while the MFT grip utilized
the finger-grooved pattern of the Tommy gun. Both grips are very well made
and highly ergonomic in nature. The
Magpul features an aggressive textured surface on both sides of the grip
while the MFT has an added grooved
back strap to its textured finger swell
for maximum grip purchase. Whatever your choice of grip style, these two
brands will fill the bill quite nicely. For
CATS shotgun ready for long range application with the stock extended and Harris
bipod deployed. This gun is capable of 3-4
inch groups at 50 yards with slugs.
Comparison view between the Fab Defence GL stock and MFT Minimalist skeleton stock. Both of these stocks offer tactical advantage
for the CATS with the GL stock offering excellent recoil reduction
while the MFT Minimalists help trim the overall weight of the gun
from the rear creating a much lighter perfectly balanced fighting
shotgun that handles more like a .308 AR PDW than a scattergun.
The featherweight MFT Minimalist stock (left) is a marvel of
engineering and ergonomics. Its weight is less than 6 ounces compared to other conventional collapsible stocks that
are ten times or more heavy without compromising comfort
and strength.
butt stock installation, you will need an
AR-15 stock extension tube (available
in Mil-Spec or commercial sizes). My
CATS gun project calls for a folding
stock to keep the overall length of the
gun to legal minimum overall length in
the folded position. With the stock folded, this 14 inch model is the same in
overall length as an AR-15 PDW with
a 7.5 inch barrel. It’s the perfect harmony between portability and accuracy.
Ideally, a compact 10-shot double stack
detachable magazine would have put a
nice finishing touch to this tactical package but that would require redesigning
the gun itself. Speaking of a magazine
fed M870; China’s Hawk Industries has
already accomplished that task and
currently producing the Type 97-1. This
model is an imitation of the Remington
pump action shotgun and available with
a pistol grip and side folding stock as
well as a bullpup version. These guns
have single stack detachable 5-shot
box magazine. A new super compact
version of this model is imported into
Canada featuring an 8 inch barrel and
a fixed stock to meet the minimum legal
overall length of 26 inches. Their current compact model features 12.5 inch
barrel with a fixed stock. Importation of
these guns to North America is handled
by Norinco Industries.
For folding stock provision, three
parts from Ace Limited will be required.
This items include the Folding stock
mechanism (FSM), the matching AR-15
receiver block (ARRB) and the CAR-15
stock block (pig nose). The ARRB is
first installed to the rear of the CAA grip/
stock adapter as you would do on an
AR rifle, followed by the usual receiver
end plate (bottom end cut off to blend
with the underside contour of the CAA
adapter). The castle nut tightens the
assembly of the ARRB to the adapter
with the top end of the Ace part flush
with the castle nut. The folding stock
mechanism is then assembled to the
ARRB with the supplied hardware.
Next step is to install the pig nose to the
folding stock mechanism with the supplied assembly screws. The CAR style
extension tube can now be assembled
to the pig nose and then tightened in
place by a castle nut once the stock
is correctly lined up with the grip and
rear sight from the rear. You may install the pistol grip to the CAA adapter
before or after you have completed the
stock assembly.
Installation of back-up sights to the
Above: Magpul AK-47 MOE grip installed on the gun compared to the MFT Engage AK-47
pistol grip. Both grips perfectly suited the CAA RS-870 aluminium pistol grip/stock adapter.
These ergonomic grips differ in style and both have a built-in internal compartment.
Right Top: ArmaLite .308 flip-up rear sight installed to the UTG saddle scope mount. This
sight is taller than a standard .223 rifle sight and will co-witness perfectly with the Pro-Mag
flip-up front sight when mounted to the CAA SGR-1. An A2 style rear sight with elevation adjustment such as the UTG copy of the LMT tactical sight can be used as an alternative (top).
Right Bottom: Mission First Tactical React Torch and Vertical Grip and Ergonomic Vertical
Grip. These vertical grips have outstanding ergonomics that position the hand as high as
possible for maximum comfort and less fatigue on the wrist while shooting. Both grips features rattle-free internal compartments shown with their rubber end caps and divider removed.
shotgun will require these two components. One is the CAA barrel shotgun
rail (SGR-1). This two-piece CNC machined aircraft grade aluminium part is
normally assembled to the front end
of the barrel like a clamp with the rail
facing down to accommodate a laser
or light. In the CATS set up, this part
is assembled to the end of the barrel
with the rail facing up to act as a front
sight mount. The lower section of the
SGR-1 (without the rail) will need to be
trimmed down in circular pattern in order to clear the diameter of the knurled
section of the Scatter Gun Technology
1-shot extension tube. This will allow
unimpeded assembly and disassembly
of the extension tube if needed. The
1-shot extension serves as a mount for
the LaserLyte tri-rail accessory mount.
This accessory primary serves as a bipod mount for accurate slug placement
at longer ranges. The side rail can also
accommodate a mini laser device if you
can find one that can take the vibration
of a 12 gauge being mounted at the
right beside the muzzle. The second
component needed is the matching
rear sight mount. A saddle type scope
mount is ideally suited for this purpose.
There are several brands of scope
mounts available for the M870 made
by Remington, Aimtech, Mesa Tactical,
UTG and others. They vary in prices,
quality and styling. For this requirement, I found the UTG to be the ideal
match for the CAA SGR-1. It is economically priced, has
great aesthetics and appears to be well made and finished.
Assembly of this part simply requires removing the two factory trigger housing pins and replacing it with the UTG supplied
hardware. Because the height of the UTG and SGR-1 is not
quite perfect on the gun, the right combination of BUIS must
be carefully selected in order for the sights to co-witness
precisely. For the rear, any AR A2 style sight with elevation
adjustment will do such as the DPMS or Lewis Machine tactical rear sights. These are fixed style sights but they leave
enough room on the saddle rail for compact optic installation.
For folding style sight, the ArmaLite .308 flip up was perfect.
This sight is slightly taller than standard .223 flip up sights.
This BUIS features a rotating disk for elevation setting and
is very well made. Unfortunately, ArmaLite has since discontinued the production of this BUIS. The next step is to
find the front sight that will co-witness precisely with the rear.
Pro-Mag’s gas block mounted AR-15 flip up sight prove to
be the ideal match for the ArmaLite rear sight. Gas block
mounted sights may vary in height depending on the manufacturer. If you are using an A2 style rear sight, its elevation
adjustment will accommodate more dimensional tolerance
between brands so you can use any gas block mounted AR15 rear sight made for the .223 caliber. The Leatherwood HiLux 3.5 MOA perfectly complemented this tactical package.
This high resolution red/green dot scope is fully waterproof
and shockproof. It comes with integral mount, flip-up lens
cover and rubber lens guard. The Model ES1 X 30TP retails
for under $100 and it’s a bargain for a rugged lightweight
compact scope that can take a beating with hard use.
Although there are many after-market forearms available for this gun made of aluminium and polymers, I elected
to utilize the original factory part which I found to have the
best fit and it is slimmer than most after-market forearms
with built-in rails (except Magpul). However, the Magpul
M870 forearm will prevent installation of a heat shield being
made higher than the stock part, therefore, it is not chosen
here. The only thing I added is the ultra-thin Yankee Hill
Machine 7-inch customizable rail at the bottom of the factory
forearm to accommodate a forward grip and light. The top
front end section of the forearm will require some trimming to
The RTG grip with the compact 1 inch diameter illumination light activated. Note the MFT BPI (Universal Equipment Mount) for Harris
bipod attachment. The LaserLyte tri-rail accessory mount is assembled to the Scattergun Technologies One-shot extension.
clear the CAA SGR-1 rear bottom loop
to allow full closing of the action. When
the matching heat shield is installed, its
bottom side will rest snuggly with the
top of the forearm thus preventing wiggle or side to side movement of the part
for a solid feel yet very smooth to operate when pumped. Depending on one’s
personal choice, I for one like to utilize
a forward grip for better control particularly with a shotgun. I can adjust my
reach at a very comfortable level with
a pump action gun much like adjusting
a collapsible stock. The market is currently flooded with all type and sizes of
forward grips to include fixed, folding,
stubby, long, flat or round and many
more in between. I have over a dozen
of these accessories made by various
companies and after trying them all on
this project gun, I have narrowed down
my choice to MFT grips; namely their
REACT Torch and vertical grip (RTG)
and Ergonomic Vertical Grip (REG) as
the perfect match for the tactical compact shotgun package. The RTG is a
combination of vertical grip and illumination mount. This beautiful grip has
many cool features. It can accommodate three popular sizes of lights from
3/4 to 1 inch in diameter including
laser device for night application. It
has a built-in secure no-rattle storage
compartment and grooved gripping
surface similar to that found on custom heat stippling for a solid non-slip
grip. Their full size vertical grip is tailored for medium to large hands and is
a perfect match for the Engage AK-47
pistol grip. Both of these grips features
finger-groove pattern and the textured
gripping surface is strategically incorporated around the grip to get the most
benefit from a comfortable non-slip
hold. To date, MFT have designed and
produced some of the finest AR and AK
furniture in the industry. These are truly
outstanding products with amazing ergonomics and original futuristic styling.
Overall, I strongly believe that MFT has
the edge over its competition especially in formulating new ideas in creating
their state-of-the-art weapon accessories. This is no secret when you take
into consideration that the company’s
design philosophy is based on heavy
input from professional weapon operators from around the globe to bring
about the most technically advance
weapon upgrades that easily met and
exceeded military and law enforcement
requirements.
Sources:
Mission First Tactical: www.missionfirsttactical.com.
Brownells: www.brownells.com
Magpul: www.magpul.com
CAA Command Arms: www.commandarms.com
Yankee Hill Machine : www.yankeehillmachine.com
Fab Defence: www.fabdefence.com
UTG Tactical: www.utg.com
ACE Ltd.: www.ace-ltd.com
Wolverine Supplies: www.wolverinesupplies.com (Canada)