After about a billion delays, I FINALLY got this
Special thanks to Aturner, too!
Although only the 1.5" rifled barrel is on the chamber,
I'm going to have a golfball, tennisball, and 3"barrel
for it at some point. The 3"� cam lever couplings make upgrading
with no flow restrictions easy.
I call it the BanjoCannon because:
1. I'm from Nashville
2. I play the Banjo
3. large diameter Banjo coupling system
1. Chamber: 1' of clear 4"
2. Barrel: 4' of clear rifled 1.5"
3. Fuel: Aturner-style onboard/offboard meter
4. Ignition: BBQ ignitor in custom modifed Aturner-style grip
5. fan: blue/green LED chamber fan with no-wires-showing electronics box
6. loading: Breech loading by 3" Banjo Cam-Lever coupling system
-Chronied in the 300fps range. The best shot was 330fps, although since
testing was very short I didn't get a great sample of readings. Further
tests will clock the mean speed with greater precision.
as seen from the rear
view of the front of the chamber
view of the banjo coupling system
breech cut on the barrel just below the banjo coupling
nice shot of the rifled barrel
view down the chamber
view of the chamber down the breech
end of the handle with the slick-lookin cut
The cannon was designed to be as aesthetically pleasing as possible
while still being functional, economical, and powerful. I eliminated
all exposed wires by making best use of the existing features of the
cannon. For example, the chamber fan's battery box is secured to the
chamber using two small machine bolts, which also function as the
electronic connections. The BBQ's wires were hidden by running them
through the 3/4" pipe and connecting them to the 1/4" bolts that hold
the pipe in place.
The handle, while it may look odd, serves two purposes by having the 2-
45 degree bends. It not only brings up the handle from the Banjo
coupling so one can grasp it easily but also changes the center of
gravity of the launcher to be the most comfortable as possible. With
the barrel attached, the cannon comfortably rests at a 30-45 degree
angle when held with one hand. The original grip
from which mine is derived (Spudtech
forum's Aturner) does not need the bends when
used with a
standard 1.5" barrel and 4" chamber (there is sufficient room between
the handle and the barrel that one's fingers are not uncomfortably
The fuel meter is also based off one I saw on a previous Aturner
cannon. It is an onboard/offboard model, in that it is locked on the
but must be disconnected from the launcher for each charging. The
charging apparatus is a propane source, regulator, ball valve, and
female quick disconnect. I chose to not use an onboard meter for cost
and simplicity. I chose not to use an offboard meter because I want to
be able to have individual meters for all my cannons so I don't have to
adjust the regulator ever. More importantly, though, with the
onboard/offboard I can use a bulk propane tank, not a throwaway
NIGHT SHOT PHOTOS!
I met with Aturner recently and got some great
stills of the cannon
shooting in complete darkness!
Frame3 Just the chamber fan
If you look closely at the barrel, you can see the rifling lands!
Sample video, 1 of 3 taken
all images, text, and other content copyright 2006
John Shell, John@NeoSpud.com