CronoArms Rhopped Barrel Kit & CroNub FAQ's

What IS this thing? What makes this kit different?

RHop is the #1 mod for accuracy in airsoft.  On that note, let's talk about accuracy and range-- with the amount of misinformation spread online, we'll break it down.

Range: The distance your BB travels while maintaining a relatively flat trajectory.
Accuracy: The level of dispersion within your groupings at a certain range.

(definition credit: BlackBlitz Airsoft, ZTWWorks)

A finished RHop kit

People often claim that any number of different boutique-priced buckings, hop up units, and even barrels gives them "better range"- this is usually untrue. But can we really blame them? There's a sea of options out there that look shiny, sleek, and sure cost a lot -- but do they really give you "better range"? The truth is that two identical BBs travelling the same velocity will always have the same range-- they'll simply travel the same terminal distance every time. So what is the point of all this crap?


The point here is not range. But accuracy.

Our RHop installs consist of a bespoke cut patch of silicone tubing that fits into the barrel's hop up window. A good patch will be flush with both the bore, and the outside diameter of the barrel. It will be chamfered on the ends to prevent pinch jams.

An in-progress patch install-- note how it "fills" the window without protruding into the barrel


Most importantly, this patch provides an elongated contact area to provide a gentler, more consistent spin to the BB; it also lets you shoot heavier BBs at a given FPS than any other hop up bucking design permits.

Critically, our kit features our in-house designed and produced CroNub.

This is a special hop up nub which is contoured and sized just right in order to take full advantage of your new RHopped barrel. Unlike the common and painstaking "eraser" or "sorbo" nub mods glued directly onto the hop up arm, the CroNub presses down evenly across the RHop patch at any level of pressure or angle of the arm. You'll receive three sizes of the CroNub to ensure fitment into any hop up unit with no modifications required.

Finally, we of course include a prepared "flat bucking" already installed onto your Rhopped ZCI barrel, which have multiple cuts to fit M4 and M14 spec applications. No mods necessary. Install the parts and go, just like normal.

We believe the CronoArms RHop barrel kit with CroNub is the best bang-for-buck kit to improve your AEG on the market.

We invite you to make the jump-- click here to navigate to product page.

***We are currently utilizing ZCI barrels exclusively in our stocked kits.  If you are interested in a different barrel or specific application(ex: Prometheus, PDI, etc), please contact us via email below for preorder information.

**For any other technical questions, please contact our tech at