K’NEX K-FORCE Build and Blast K-5 Phantom Review

The smallest K-FORCE model tells the K'NEX blaster story.

KNEX K-Force K-5 Phantom
K’NEX K-Force K-5 Phantom.

As we're waiting for all the new blasters announced at Toy Fair to finally hit store shelves later this year, a keen observer might note that we have yet to post a review of any current K'NEX K-FORCE Build and Blast models. And that's a shame, because the concept of modular, more customizable blasting is certainly coming into its own with the growth of Nerf modding and Hasbro's own Modulus line of Nerf blasters.

So before the new K'NEX blasters land at retail, we thought it appropriate to go back and review one of the very first models to bear the K-FORCE name: the humble K-5 Phantom blaster.

January 3, 2014 was when the K’NEX team in Hatfield, PA first started working on the idea of a build-it-yourself line of blasters. And it took them less than a year and a half to go from inception to retail delivery--a fairly incredible feat, considering some Nerf models are in development for 2, 3, or even 4 years or more! But we've toured the K'NEX factory and seen first-hand the impressive engineering and production put into the K-FORCE models, and have spent more than a year playing with various iterations of the concept to see whether or not this whole “Build and Blast” concept has merit. It’s one thing to talk about the idea of a blaster that can be made from construction toys (and really, what boy hasn’t tried this already?), but it’s quite another to deliver a product that ostensibly delivers on the promise of being both a good construction toy while also being a good blaster product.

The K'NEX K-FORCE K-5 Phantom that is the subject of this review was provided to us before any K-FORCE models had even hit store shelves, and it just so happened that it is actually a UK-exclusive model. Fortunately, the K-5 Phantom is a very close cousin of the K-FORCE K-10X that has been available in the US, and the functionality is identical.

So this review is essentially an overview of several models--including much of the broader K-FORCE line that shares the same core building elements. The differences between models like the K-5 Phantom and the K-10X, for example, are mostly in price, style, and parts count (53 for the Phantom, 91 for the K-10X). Simply adding or removing parts from either unit will allow you to create the alternate model. And since the Phantom is the smallest model in the K-FORCE line-up, we thought it made sense to start with the most simple, most “pure” expression of what K-FORCE is about.

Design and Ergonomics

It must be said that every blaster in the K-FORCE product line has a distinctly “pieced-together” aesthetic, which is both good and bad. On the one hand, the more complicated the blaster design, the more pride-of-ownership one might feel in having successfully built such a complex machine (not unlike the massive roller coasters, Ferris wheels, and other familiar K’NEX construction sets). On the other hand, the bright, multi-colored pieces never fail to reinforce that these are toys, first-and-foremost, implying both fragility and a lack of seriousness. And while parents will undoubtedly like the visual distinction from real firearms--not to mention the inherent building aspects--the target audience (boys in their teens, and boys soon to be in their teens) don’t want blasters that look like toys.

They want blasters that resemble the real thing because, let’s face it, they’re playing “war,” not “circus.” Hasbro has walked that tightrope quite cleverly with their Nerf blaster designs through the years, but even they have inched closer and closer to a more tactical-inspired aesthetic.

One complicating factor for K’NEX is how much of the product is made of rods and connectors versus custom pieces made specifically for K-FORCE. During a visit to K’NEX HQ, we were shown early prototype blasters that were made almost entirely from existing K’NEX pieces (sans firing unit). But the story goes that when these models were given to the CEO of K’NEX, he instructed the design team to create custom pieces for the handle and trigger areas that were more comfortable than what could be built using traditional K’NEX rods and related pieces.

The result was a blaster design that was certainly more comfortable in these areas, but was decidedly moving away from being “pure” K’NEX. And that instantly raises the question: where do you stop? For now, it’s the firing unit, darts, handles, triggers, and a few other minor components that are specific to K-FORCE. But on a blaster like the K-5, the overall feel is about 50% K’NEX rods and connectors, and 50% blaster-specific pieces. Larger kits certainly add a higher percentage of core K’NEX elements, but the “blaster” parts are decidedly non-traditional. Should K’NEX have gone even further, and made scopes, shoulder stocks, clips, and other elements that are outside of the traditional “rods and connectors” K’NEX design language? It certainly would have helped reduced some of the “construction toy” feel, but it would have also made it less uniquely K’NEX. Perhaps a more unified color palette would have been one solution to the problem–less visually disparate elements to take away from the fundamental design of the blaster itself. It’s a tricky situation, but one we feel has yet to be fully resolved, and future products appear no different.

Fortunately, the aforementioned tweaks to the handle and trigger aspects of the K-FORCE product line have resulted in a more ergonomically refined product than would have been possible otherwise. The handle, while a little thin for adult hands, is certainly more comfortable to hold than anything made of K’NEX rods would have been. And the trigger is likewise smooth and pleasantly benign. Our only real ergonomic gripe relates to a piece of structural bracing that interferes slightly with the priming rod at the back of the firing unit on this particular blaster–when pulling back on the ring attached to the end of this rod, the bottom of the finger that pokes through the ring is obstructed slightly by a horizontal cross-member. It’s virtually impossible to ignore touching this cross-piece during a full draw (required to properly prime the blaster), and causes hesitation when attempting to fire rapidly.

Lastly, when it comes to aspects of both design and ergonomics, we should mention that, on occasion, the mostly decorative scallops formed by rods on each side of the blaster had a tendency to pop-off. In addition, the piece that acts as the trigger also came loose on more than one occasion, sliding down slightly from the rod to which it was attached. Note that we tested a total of five (5) samples of the Phantom we were provided, and it was the same with each blaster, not a defect resulting from an improper build. Still, neither issue significantly detracted from our ability to use or enjoy the core product.

Use and Performance

Aside from the aforementioned issues with a part or two coming loose, the K’NEX K-FORCE K-5 Phantom is solidly constructed (assuming the end-user assembles things correctly, of course). We won’t go into the full building and assembly process, but anyone with construction toy experience should have the K-5 kit put together and ready-to-fire in about 10-15 minutes, maybe less. That’s assuming, of course, that one doesn’t fall prey to the temptation of modifying the design at all by adding or removing parts of his or her own desire along the way. It’s a strange thing to say, but K’NEX may now be the one blaster-building company that actively encourages modification of their products… using official pieces from the K’NEX catalog, of course!

If we go one further to answer the durability question, we would be inclined to say that K-FORCE blasters are rugged enough for casual use, but hard-core gamers will likely be better-served by offerings from mainstream brands, lest they risk a part or two popping-off during the heat of battle. Ironically, the individual K’NEX pieces themselves are nearly indestructible, and even have a self-sacrificing quality upon impact (a piece or two might pop-off, largely absorbing the blow) that hard-plastic models from Hasbro, Mattel, and others can’t claim. Still, we can’t help but shake a certain air of fragility that surrounded our tests of the K-5 Phantom. Nothing actually “broke,” but it was very easy to handle the product in such a way that a part would come loose, pop-off, or otherwise remind us that this is a construction toy first, blaster second.

As for the core performance of the blaster itself, we were impressed. In our indoor testing, we reached a very respectable maximum shot distance of 87 feet! But perhaps even more impressive was the fact that most shots were very close to this measurement, with mid-80 foot ranges easily achievable from an arc of 30-40 degrees, and more than one shot reaching just shy of 90 feet. But perhaps even more impressively, the K’NEX darts had shot groupings that were significantly tighter than standard Nerf Elites (which we also tested with the K’NEX blasters). Nicely done, K’NEX!

Those distance findings were backed-up by our dart velocity testing, as well. Our chronograph told us the K-5 Phantom launched darts with an average speed of 73 feet-per-second. We recorded a low of 51 feet-per-second, and a high of an astonishing 97 feet-per-second (!). That 97 feet-per-second recording may have been an anomaly, but even so, it's one of the fastest stock dart velocities we have ever recorded, and demonstrates just how potent even a fully stock K-FORCE blaster can be, even without any spring modifications or other shenanigans. Of course, the average velocity of 73 feet-per-second is much closer to what we expect in typical use, and this velocity falls right in line with most of the better Nerf products we have tested recently.

When it comes to rate-of-fire, the best we could manage with the K-5 Phantom was 22.77 seconds to load and fire 10 darts, resulting in a fairly low rate-of-fire of just 0.43 darts per second. This was made especially difficult by the aforementioned, horizontal cross-member that impedes the priming ring’s pull-back action. That being said, darts aren’t hard to load, and the priming mechanism itself works without issue. We know that additional models with motorization, clips (magazines), etc. are on the way, so it’s entirely possible future K-FORCE designs will fair better in this regard.

Value and Fun

We can say, without hesitation, K’NEX K-FORCE Build and Blast products are a good value. Where else could you find a blaster that performs as well as contemporary Nerf products, is largely cross-compatible with competing products, has a virtually endless upgrade/expansion path, is made in America, comes from an established brand, and is just as much a construction toy as it is a blaster? The answer is, quite literally, “no where.” And on top of that, prices for K’NEX K-FORCE blasters are not much more than you’d pay for a traditional blaster by itself, even if you completely ignore the fact that K-FORCE is also a full-fledged construction toy that is compatible with the majority of K’NEX rods, connectors, and other pieces that have been on the market for decades.

We can also say, with nearly equal unanimity, that K-FORCE blasters are fun. Sure, the core blasting aspects are nothing particularly special (even if the performance is a notch above the competition), but the “build-it-yourself” factor is unique, engaging, and thoroughly fulfilling. It gives non-modders a hint of what that community finds so enjoyable, in the sense that you get to be more “hands-on” with your blaster (even if you’re not actually experiencing the satisfaction of increased performance or heightened visual appeal, for instance). Of course, it’s the future potential of K-FORCE–what inventive consumers end up doing with the products using additional parts from the K’NEX catalog–that is perhaps most exciting.

So, K-FORCE is fun, and undoubtedly a great value, but it’s not without a few lingering questions. The biggest of which is whether the Build and Blast concept is capable of propelling K-FORCE beyond an existence as a construction toy over-achiever. That is, can K-FORCE grow and improve to one day reach full-fledged blaster greatness, or will it simply find stasis as a cross-category curiosity? It’s too early for anyone to answer those questions, even with the new products that will soon be released. But we can at least say the team at K’NEX has achieved something admirable with their first series of K-FORCE products–they’re fun to build, perform well, and are a great value for the money. We look forward to tracking their success in the market, and especially in building what comes next!


  • Building aspects add value over-and-above competitors
  • Surprisingly well-engineered for a freshman effort
  • Impressive range and accuracy


  • Cocking ring too close to structural element on pull-back; slow firing rate
  • Some pieces prone to coming apart during use
  • Handle is on the small, narrow side