Rear Loading Super Shell -- 86 FPS -- 3x Short Dart (or Elite) -- NERF Doom Cannon

>>> up to 86 FPS with the stock NERF Doom Cannon <<<

Rear Loading OPEN SOURCE SuperShells:

3x short dart (or Elite)
1x short dart (or Elite)

First of all, a huge thank you to BuffdaddyNerf for designing and releasing the first working OPEN SOURCE Supershells for the Doom Cannon :)

As I wanted a SuperShell for 3x short dart, I made a remix that’s open at the back, allowing you to load the short darts directly from the rear into the barrel’s tightening ring.
(This eliminates the need for the fiddly process of loading the short dart from the front using a ramrod)

I’ve also slightly increased the diameter of the front barrel section so that the dart can fly through as smoothly and with so little frictional resistance as possible, whilst still being accelerated by the residual air pressure behind it, despite the air restrictor.

Elite darts will, of course, also work in this shells. 
I’ve also added a version with slightly wider barrels specifically for Elite darts.

Max. FPS test RearLoading_SuperShell_(3xShortDart)
(stock Doom Cannon with stock spring and air restrictor):

X-Shot short darts (red) = ~86 FPS (average  ~83 FPS)

Dart Zone short darts (Ember) = ~81 FPS (average  ~79 FPS)

original NERF Elite darts = 81 FPS (average ~78 FPS)

(The original NERF SuperShells that come with the blaster reached 50 - 55 FPS with the NERF Elite darts during my tests)



>>> As the air restrictor on this shell remains functional, it can also be used to load and fire one or two darts. The AR then "closes off" the air duct to the unloaded barrels.
However, the resulting FPS gain is limited and amounts to just around 3–5 FPS.
But if you’re pressed for time and want to get a shell ready to fire quickly, it can be quite useful ;)

Rear barrel segment (tightening ring): D = 12.8 mm
Front barrel segment: D = 13.2 mm

Click here to see my other Supershells for the Doom Cannon.

• Update 22.7.2026:
  I’ve added an alternative shell for ELITE darts with barrels that are 0.1 mm wider.
  If the short dart version is a bit too tight for your full darts, you can use this version.
  This shell makes rear loading of Elite darts much easier and prevents full darts from getting stuck.
  Unfortunately, the downside is a FPS drop of 3-4 FPS with these slightly wider barrels.
  
  

• Update 23.7.2026:
  I’ve added another shell with just a single barrel to shoot single darts at a slightly higher speed.
  Because the barrel is limited by the length of the shell – only 77 mm – the large volume of the plunger tube can only be utilized to a limited extent.
  But at least you can achieve up to 101 FPS with X-Shot short darts, using the stock Doom Cannon.
  

-----------------------------------------------------------------------------------------------------------------------------

The files are already pre-oriented.

My print settings for PLA:

0,2mm layer height
2-3 walls
5-15 % gyroid infill
7 top and bottom shell layers

If you don’t plan to throw the Supershells around on the hard floor and your printer produces airtight walls with a 2-wall setting, a 2-wall setting and 5% infill are sufficient. This significantly reduces printing time and filament consumption. I ended up printing my Supershells during the tests using these settings ;) That way, you only need just approx. 75 grams of filament instead of 100. 

Thanks to BuffdaddyNerf for the files I could use for this remix.