Friday, August 20, 2010

Knoxx SpecOps Folder Review

Knoxx Review, SpecOps Review, Buttstock Review, Stock Review, Recoil Reducing Review, Blackhawk Review
Last year I purchased a Mossberg Maverick 88 Security 8-Shot Shotgun.   I wanted to get some type of pistol grip stock to turn the gun into a cruiser version of a shotgun.  I selected the Maverick 88 shotgun because it was the economy line model from Mossberg which allowed me to afford buying some accessories which was cheaper than actually buying a Model 500 Cruiser.  A buddy of mine told me about the Knoxx recoil reducing stocks, so I had to check them out.

Before I go any further, I want to say that I'm 6' 2", 220 pounds and wouldn't consider myself a wimp.  My interest in recoil reducing is two fold.  First, the recoil reduction allows a more pleasurable shooting experience for me while at the range and secondly, it allows my home defense shotgun to be something that my wife is actually willing to shoot more than once.  Training is a key component for using any gun in a true defense situation, and the more you enjoy shooting, the more you are willing to train.

As I started looking at the Knoxx stocks, I found they had several styles to choose from; the Breachersgrip, the Folder, and the Adjustable.  If you check out the links for each item, you will see they took you to the Blackhawk website.  I'm not sure of the details, but some how Blackhawk is affiliated with Knoxx Industries because if you go to, it takes you to Blackhawk.

Breachersgrip                                        Folder                                            Adjustable    

My original thought was to make the shotgun a cruiser style, but I decided to go with the Folder instead because it wasn't that much more ($20) and gave you the option of shouldering the shotgun if desired.  I ended up purchasing the Knox SpecOps Folder from for $88.46 plus S&H.

Since I purchased this stock before I started doing online reviews, I no longer have the original packaging.  If you purchase one today, it will most likely come packaged as shown from the Blackhawk website in the photo below.

The following information in italics was taken directly from the Blackhawk website. Also, throughout this review, all information in italics represents the manufacturers advertised specifications and features.  All of my review comments will always be in plain text.

Based on the highly acclaimed Knoxx SpecOps Stock™, this sleek folding pistol grip stock takes the pain out of shooting magnum buckshot and slug loads, even with the stock folded. The sturdy soft-rubber coated folding wire-frame stock with integral rubber butt pad is easily folded over the top of the receiver. This allows for compact storage and increased maneuverability in tight spaces, such as vehicles, motorcycles, hallways and entryways. 
The SpecOps Folder™ pistol grip contains the unique Knoxx recoilreducing mechanism. The patented recoil-reducing mechanism reduces muzzle flip in addition to taming recoil. Shooters testing the SpecOps Folder™ with Magnum Buckshot loads have found that there is very little discernible recoil in either open or folded positions, with virtually no muzzle flip. The patented Knoxx SpecOps Folder™ shotgun stock cuts perceived felt recoil by over 65%.
Integrated recoil compensation system
  • 65 % reduction in perceived felt recoil
  • Eliminates painful recoil in the open or folded position
  • Eliminates shooter fatigue & recoil related wrist or hand injuries
  • Increased accuracy and faster follow-up shots
  • Cuts muzzle rise to get back on target faster
  • Increased confidence & effectiveness in shotgun utilization
  • Maintain a better cheek weld compared to other folding stocks  
Integrated Metal Sling Stud for Easy sling installation  
Ergonomic Pistol Grip with Integrated Non-Slip Texturing for Improved shooter control and comfort 
Single Bolt Installation (Pre-installed bolt & lock washer) for Quick and easy single bolt installation

You can find the Owner's Manual at this link.

The next set of photos show the details of the stock after it is removed from the packaging.  Blackhawk/Knoxx states the following about the build of their stock.
  • "Super Tough" Polymer and Alloy construction
  • Well proven materials for years of rugged and reliable service
  • Corrosion resistant materials for use in all weather conditions
  • Built tough for law enforcement and military environment
  • Integral rubber butt pad for improved comfort
  • Does not inhibit site picture when folded
  • Rubber coated wire frame for improved comfort in cold or hot environments
I would have to agree that this stock does seem well built and should last for years. The pistol grip portion is some type of polymer material, the portion that attaches directly to the shotgun seems to be some type of aluminum alloy, and the butt cap and folding wire frame appear to be some type of steel alloy.  The wire frame is covered with a rubbery material.  Again, I don't think anyone would be disappointed with the build of this stock.

  •  Simple & Fast Folding Mechanism 
  • Easy one hand operation of folding mechanism
  • Simple to fold open or closed even under stress or while wearing gloves
  • Self-locking mechanism eliminates the need to operate or engage locking buttons or tabs
  • Simply squeeze and fold…it’s that easy!
  • Compact Design
  • Reduced overall size for improved storage options/ ideal for quick use
  • Ideal for tactical entry or home defense shotguns 
  • Length of Pull: 14”
I also agree that it is a simple one handed fast motion to go from folded (closed) to extended (open) positions.  You squeeze the sides of the wire frame together near the pivot and rotate.  The folding stock will automatically lock into position for both the open and closed positions.  They have shown this in the Owner's Manual with actual photos.

Before I installed the stock, I wanted to get the weight of it.  The Knoxx SpecOps Folder weighed in at 2.08 pounds.  The weight of the stock on the Mossberb Maverick 88 was 0.96 pounds, so the net weight added to the shotgun was 1.12 pounds.

Installation is simple and again it is covered in the Owner's Manual.  First you remove the butt pad by unscrewing the two bolts.  Next you remove the stock to receiver attachment bolt.

When you remove the stock, the end of the receiver looks as follows.

You can see how the receiver will interface with the stock by looking at the photo above and below.

You line up the stock and receiver and thread the attachment bolt into the receiver with a long Allen wrench then tighten securely.

The two photos show my stock installed on my Mossberg Maverick 88 Security 8-Shot Shotgun.  You can see are review of this shotgun bo going to this link.  Installed on the magazine tube is a Laserlyte Shotgun Tri-Rail, with a PLA118 Flashlight Mount and an Inova T4 Flashlight installed.

The next two photos give you a good closeup of the pistol grip area.

One thing I want to point out is that the good ergonomic location of the bolt lock lever on the left side of the gun becomes a little cumbersome to release the bolt with the stock installed.  You can no longer do it with your middle finger and you can not reach it with your thumb when you have a correct shooting position on the pistol grip.  You have to rotate your hand around the grip until your thumb can reach the lever.

The next feature to evaluate is the recoil reducing feature. Just to be clear, when I talk about this recoil reducing feature, it is in terms of "felt recoil". Felt recoil is your perception of the recoil. The addition of springs helps spread the recoil over a longer period of time which gives the rifle a softer feel and thus less felt recoil. For more information on recoil, you can read this article from Wikipedia.

Knoxx has placed a spring inside the stock handle that attaches to the upper slide portion as shown in the photo below.  As the upper portion slides back, it causes the spring to stretch.

You can see the spring inside the handle shown in the photo below.

The next photos show the stock in the normal position and in the fully compressed position.  It appears to compress about 3/4".

Since I don't have any way to measure the actual reduction in recoil, I wanted to check and see how much the upper portion of the stock actually moves when shooting the shotgun.  To do this I setup some simple tests with aluminum foil.  In this photo I show tape placed on each side of the stock and foil bridging between the tape.  If the upper moves back, it will bend the foil and the bent foil will keep it's shape and give an indication of how much it deflected.

After shooting the shotgun with Knobel Sports #4 Buckshot in 2 3/4" 12 gauge, you can see how much the upper portion deflected based on the change in the foil.  Basically, the upper portion of the stock deflected most of the travel of the stock, which is a good thing.

Next I wanted to try to get a better idea of how far it deflected, so I set up the same test with a smaller piece of foil bridging over the stock.

Again, the upper portion deflected most of the range during the next shot.  From my observations, I believe it utilized the entire travel of the stock.

From this, I can say the recoil reducing feature works.  My impression of the felt recoil was that it is less than shooting a stock without this feature.  I can not realistically give you a % reduction, but I can say I'm happy with this feature.

Now for the bad part.  The wire frame is very uncomfortable to shoot if you are using standard sights on a shotgun.  What I mean is that when you look down the sights of a normal shotgun, your cheek is directly against the wire frame of the stock.  Since this wire frame has to be wide enough to fold over the receiver, it extends out much further than a normal stock would extend.  When you fire the shotgun, you feel it against your cheek more than your shoulder.  If your plan is to have a gun you can shoulder, I would not recommend this stock, but instead I recommend the SpecOps Adjustable model. 

If your shotgun has some other type of elevated sight, the wire frame may not be an issue because your cheek would be higher above the wire.  You can see about how much of a sight window you would have with the stock folded.  There is about a 1" open area between the receiver and the stock.

Bottom Line:
The Knoxx SpecOps Folder Stock is a quality product and clearly reduces recoil.  If you believe you will shoulder your shotgun most of the time, I would consider the Knoxx SpecOps Adjustable Stock since the wire frame of the SpecOps Folder is uncomfortable to shoot with normal sights.  Now that I have owned this stock and taken it to the range several time, I think the other model may have actually been the one best for my needs.  On the other hand, I really like folding the stock into the compact version and keeping it in a handy locaiton at home.


  1. Thanks for the great review. It is very informative.

  2. well i like the look of the stock but whenever i shoot magnum loads fromm my mossy 500 the roller connected to the lever arm in the pistol grip jumps over the retaining post and either locks up the mechanism or completely dissengages it. Little upset. maybe i got a lemon?

  3. Nut'nFancy did a review on the SpecOps Adjustable and found the cheek impact even worse than what you describe, together with a wobbly squirming motion that interfered with accuracy. Performance was not improved. Maybe the standard Blackhawk recoiling stock? A Limbsaver might be the best bet, as it's not mechanical, but folks have said it cuts back recoil a lot.

  4. I have the SpecOps folder and I agree with everything that the reviewer has posted. It's just slightly too long and ever so slightly uncomfortable. I didn't feel it in the cheek at all but the wire stock , lack of real butt pad, bit me in the shoulder once. It was a poor shoulder mount on my part I admit.

    It's STILL A GREAT PRODUCT. I felt the difference and enjoy shooting this stock. Just have to make some adjustments to the butt pad. (wrap it with something a bit mroe thick like a rag or cotton cloth)

    From the hip and one handed this is easy as pie to shoot. My grandma could do it. :)

  5. I installed the SpecOps adjustable model on my Remington 870 and I have to say that it punches you in the face every time. Felt recoil to the shoulder is well-mitigated at the expense of your face. I agreed with Nutnfancy's video review when I saw it, which was a year after purchasing and using the Knoxx stock. However, the adjustable LOP is the reason I keep it on for home defense; the tactical advantage outweighs face pain for that purpose.

  6. Thank you for the review. I too am looking at the Mav88 plus pistol grip for home defense, so it was good to read. What did your wife think?

  7. It didn't seem to make too much of a difference with my wife. I think the wire stock was the deal breaker for her.

  8. Hi Kevin, thanks for the review. I need to know: how is the metal round cap (Where you press to fold or open stock) attached to the plastic part? Bolt? Glue? Retaining pin? See where/ what I mean here:

    Hoping to hear from you, and a photo too, if possible. Thanks.

  9. I was out of town over the weekend. I will take a look at it tonight. I think I have it figured.

  10. To remove the metal cap, you need to remove the set screw on the lower surface of the cap using a very small Allen wrench. With the screw removed, you can twist the cap about 1/8 turn and then it pulls off the polymer part.

  11. Thanks for the review. I just purchased one for my 870 but almost wish I would have found this review first. I'm hoping that shooting it with the frame open is not as uncomfortable as some are describing here. On that note, I see from the question above that the back cap holding the folder can be removed. What is under there? If removed would you be able to use it just as a pistol grip (breecher)? Thanks.

  12. Excellent. Well made. The most versatile stock, allowing the shotgun to be fired with the stock folded breacher style, or quickly and easily unfolded to be fired from the shoulder. Folded it is the most compact stock I have found - I have transported my shotgun strapped to the sissy bar on my cycle - the muzzle of my 19 inch barrel barely extending above. THIS IS NOT A TOY designed for extended range sessions and target style shooting that requires a precision cheek weld. It is an ideal stock for home defense and other tactical applications. Felt recoil is reduced notably. Wish I could find another.

  13. Hello, newbie here, are you able to fit a scope on top without the stock hitting it? Also wondering if a side shell holder would also get in the way. Thanks!