Nerf just released a new tripod mounted fully automatic Nerf gun with dual reciprocating barrels called the Nerf N-Strike Elite Rhino-Fire Blaster. With the modifications that I made to the Nerf Vulcan Xtreme, the Rhino-Fire seemed to be an ideal candidate for conversion to an HPA airsoft gun. Since I’ve done a dual PolarStar Fusion Engine Nerf gun already, I decided to give the Rhino a try using Wolverine Airsoft SMP HPA engines.
The Rhino uses motorized flywheels to shoot the Nerf darts, so the firing mechanism was relatively simple which left a lot of extra room for Nerf to add a mechanism to reciprocate the barrels, which ended up taking the majority of the space withing the Nerf gun housing. The Wolverine SMP is a very small HPA engine designed to fit within a gearbox shell, so it turned out they were the perfect size to fit within the Rhino.
I utilized some of the same techniques from recent a M2 and FN 30 builds and created 3D printed blocks to support the engines and integrate a custom hopup. An adjustment screw was added to the back of the support blocks, between both of them, to allow the cross angle of the engines to be adjusted.
The stock trigger switch was removed and replaced with several leaf microswitches. Once switch turned on the box mags and reciprocating barrels, and one trigger switch for each SMP. The stock trigger was a multi stage sliding switch and it just didn’t work reliably as a trigger switch. I used my SMP mini circuit boards to link the trigger and full auto switches to the SMP wire harness. Two SP3T slide switches were added so allow each SMP engine to be in safe, semi, or full auto mode. To make this work I modified the mini circuit boards and added a diode to allow the slide switches to handle all three modes using 3 wires.
The two drum mags were modified to use a MAG brand box mag BB feed mechanism. 3D printed parts were used to create a mount for the feed mechanism as well as make a cover plate and fill port. Each drum mag will hold about 4000 bbs and the MAG feed mechanism can easily reach 40 rps, especially if 11.1v lipos are used.
The Wolverine SMP powered Nerf Rhino-Fire is a very fun but frightening airsoft gun. The larger hollow out barrels of the Nerf gun amplify the sound of each shot making this HPA airsoft gun one of the loudest I’ve used. Combined with the relatively high rate of fire delivered by the SMP, the cacophony behind the two laser streams of BBs, anyone trying to oppose the Rhino dual SMP would certainly know trouble was heading their way!
Here are some images of the stock Nerf Rhino internals and externals, for reference.