Adaptive Tactical Sidewinder Venom Kits

sidewinder kit

Adaptive Tactical is now offering the Sidewinder Venom shotgun enhancements as home conversion kits.  These kits will work with Mossberg 88, 500, 535, 590 and 835 shotguns.

sidewinder kit

There are three kits:  one with a five round box magazine, one with a 10 round rotary magazine, and one with a new M-4 style buttstock and 10 round rotary magazine.  The first two kits are available in black only and are priced at $219.99 and $279.99 respectively.

sidewinder kit

The Venom -SE 10 kits are available in black, A-TACS, MultiCam and Tiger Stripe Digital Desert colors.  The MSRP on the black kit is $339.99 while all of the other camo patterns retail at $399.99.

sidewinder kit

It should be noted that while these Sidewinder Venom kits are very similar to the Sidewinder conversion kits made by Knoxx prior to its acquisition by Blackhawk, Adaptive Tactical states the “new Sidewinder Venom magazines and related components are not compatible or interchangeable with the original Sidewinder magazines and conversion kits.”

Richard Johnson

An advocate of gun proliferation zones, Richard is a long time shooter, former cop and internet entrepreneur. Among the many places he calls home is


  • Risky

    Black Ace’s Remington/Mossberg receivers that accept Saiga 12 mags will pretty much make this junk obsolete. More expensive at 5 bills… but looks to be worth the difference compared to this goofy contraption – if you want a detachable mag pump shotgun, anyway.

    • TLW

      The 5 rd mags for this thing start at $70 and the 10 rd mags start at $130. Saiga mags are much cheaper.

      • But, someone like me, being in Canada, can’t own a Saiga (But I’m free to own most other Semi auto shotguns!?!?!)

        So this would be pretty cool.

        • JumpIf NotZero

          Be careful of what you wish for 😉

          • Huh?

          • JumpIf NotZero

            Saiga actually kind of suck… And by kind of, I mean totally suck unless you put a lot of money into them. They’re about 1/2 “vodka specials”, the grinding of parts to make fit is beyond anything that should be required in the year 2000, the guns require gas port work, they require a mag well, magazines must be custom fit to each gun. Saigas suck.

            This isn’t even getting to the fact that a 12ga shell is NOT designed for a box mag, that the manual of arms is far behind a benelli or 870, you lose ammo change overs and easy to access chamber to clear malfunctions… I owned a Saiga, best gun deal ever made was to sell that garbage.

            Be careful what you wish for, you just might get it.

          • Tim U

            The real draw of the Saiga is that it is the same manual of arms as the AK platform. If you don’t like AK rifles, you’ll hate the Saiga. There is no need for one of the magwells from a third party, and I have NEVER had an issue buying a Saiga magazine, loading it, and running it solid in mine.

            Aside from the 922r compliance parts, the most money I’ve sunk into mine in parts to improve reliability is definitely under $100 – MD Arms gas reg + lighter spring for birdshot…. and the lighter spring isn’t needed if you want to shoot buckshot or slugs.

            Sure, the tube-feds have some advantages, including ability to quickly swap ammunition types. But if all you want is to dump buckshot at the target, Saiga is the fastest way to get that much #00 buck downrange in the shortest time. Reloads are far faster than tube-feds.

            Sorry, not buying the Saiga hate. Niche item, yes. Reason to hate? No.

          • Pfft, even if I wanted one I couldn’t own it. Canada has banned nearly all AK models, and by nearly all, I mean all but 3, all made by Valmet, all based on the RPK, and all costing about $5000 because of the lack of availability.

  • Matt

    If you need a kit to turn your shotgun into the shotgun you want. Maybe you bought the wrong shotgun?

    • JumpIf NotZero

      Agreed. I’ll add that of you think you want a box mag shotgun, you don’t actually know what you want. All the things that make shotgun mags great are lost with box mags. See my Costa Shotgun AAR here on thefirearmblog if you want details.

      The short version is if you need more than 5-6 rounds, you need a rifle. But shotguns offer amazing versatility if you know how to use it.

      • erwos

        I read that AAR, yet still have no idea what you’re talking about. Yes, it’s easy to slam in a single “special” round for when you need it in a tube magazine… but there’s also nothing stopping you from just carrying a box mag with slugs in it.

        If you just need to dump out the most buckshot possible at a target in the shortest time possible, platforms like the Saiga 12 are hard to beat.

        • alex

          as did i, what are you specifically referring to?

    • John184

      I guess the KSG could be great if you wanted high capacity and a pump action, but the Firearm Blog’s review doesn’t sound too favorable. A shame really, the design is promising.

  • Cheeze Whiz

  • Clodboy

    Looks like something straight out of Fallout. Seriously, isn’t the primary reason to pick a pump action the reliability factor? And isn’t reliability (or rather lack thereof) usually the biggest drawback with shotgun drum mags?

    Then again, some people like to own exotic conversion kits just for the coolness/fun factor, in which case I say more power to them, because it does look pretty neat.

    • sianmink

      reliability in that it doesn’t matter if the powder charge is soft or you’re firing some special purpose round that won’t cycle an auto.
      Working a pump reliably under stress takes practice practice practice.

  • Michael Pham

    I’ve always been of the opinion that the pump action shotgun was one of the last refuges of the tubular magazine and for good reason. It just makes sense, from the fact that shells aren’t pointy (no accidental discharge), have plastic hulls (don’t hold up well to spring tension), and they’re large caliber (so a box magazine needs to be huge). I mean that rotary magazine just holds ten rounds.

    Still, hey. Do what you want. Its not like you’ll find a Valtro PM-5 anywhere.

    • JumpIf NotZero

      Pretty much this. 12ga are not designed to feed/be stored in box mag. Anyone that’s owned one and seen 12ga deform into ovals then leak their filling had figured this out pretty quickly, amazes me anyone would trade a tube mag for a box when dealing with large plastic hulls.

  • Martin M

    That’s an awful lot of cash for an awkward and clumsy setup that only increases your capacity by 1 or 2 rounds. I’ll stick with a nice, clean, compact 590 and pass on the clunky, over-priced gimmick.

  • FourString

    I’d like to see one for the Mossberg 930. And the price for the mags, please, bring that down…

  • Russell Phagan

    I had one of the Knoxx sidewinder kits back in 2005. Total piece of shit. The fitting required, more force being required to operate it, and the fore end being so far forward all made it suck.

    The entire concept of making the mag feed through the tube is flawed. The mechanism compresses the shell as the magazine tube spring would until the pump is all the way to the rear and the shell intercept latch releases it. The shooter is compressing te spring inside the magazine tube/well with each pump.

    The black aces tactical receiver that accepts saiga-12 mags is a much better idea.

    • Adaptive T

      Russell. Thank you for the honest feedback on the Knoxx Sidewinder. While the underline concept is the same as the Knoxx Sidewinder, the new Sidewinder Venom has been completely overhauled. The composites have been updated, the magazine well and release lever re-engineered, and the smoothness of the action or “force required to operate” has been vastly improved to match that of a factory pump action. If your preference was magazine fed shotgun, you would be pleased with the construction and performance of the new system.

  • I can actually see this making sense for small AOW and SBS type shotguns where your tube magazine is severely cut down, limiting capacity. But that’s pretty much it.

  • I had one of these on my Mossy 500. Shells had a tendency to eject from the magazine if you fumbled the reload. Sometimes it would “stick” and required a hefty lock back to actually chamber something. the aluminum cap of the replacement magazine tube was so soft that the barrel retaining knob stripped clean out after a couple shots. the Knoxx stock was great but the Sidewinder? Barely broke even for the price of the kit on Gunbroker, much less the cost of the shogun. Interesting idea, but wasn’t worth the cost or the problems.

    • Adaptive T

      Rick. Thank you for the honest feedback on the Knoxx Sidewinder. As I stated in response to an earlier post, while the underline concept is the same as the Knoxx Sidewinder, the new Sidewinder Venom has been completely overhauled. The composites have been updated, the magazine well and release lever re-engineered, and the smoothness of the action or “stick” you described has been vastly improved to match that of a factory pump action. The new version utilizes Mossberg factory action bars and mag tubes to address the issues regarding component wear. Thank you again for the feedback and positive feedback on the Knoxx Stocks.

  • GlockLove

    Agreed the only shotgun id use this on would be one of those Serbu super shorty’s but it looks like you would have to cut down the pump part on one of these kits for it to even work right…this just doesn’t look too promising to me . if anyone needs more than 8+1 in there shotgun than maby you don’t need a shotgun…also why not just spend another 250 and get a saiga 12 idk im not trying to stright up bash this kit it looks really cool dont get me wrong but for the money i dont see anybody buying a 400$ kit for there 250$ shotgun but this would make a SBS look sweet and super tactacool