This project is the result of about a year of tinkering with shell designs and I have reached the point where it has gotten so good that its very hard to improve, but I would appreciate any ideas people here have.
The first section, the "Flare" is built out of the bottom of an empty, 1-lb sour-cream container, which has been cut to fit the 3-inch barrel with an impressively air-tight seal.
Container before cutting.
You can achieve this easily by placing the container bottom down into a 3-inch PVC barrel, then using a pen to mark a circle flush with the PVC pipe. Cut along the line. Now you have an almost perfectly air-tight piece. Some extra trimming may be necessary, but this should get you very close.
Container after cutting.
The second part, the "Body" is a section of Pringle's can that has been cut in several ways.
First, slice off the rim that holds on the Pringle's can. Wrap it all in JUST ONE LAYER of duck tape, no more. We are NOT trying to get it air tight here, the tape is just to strengthen it. Slide the Pringle's can down a 3-inch pipe, it should fall easily.
Insert the Flare piece, bottom first, into the open end of the Pringle's can, it will go in a little way and then stop. Measure 5 inches from the outer edge of the Flare up the Pringle's can. At the 5 inch point, cut the Pringle's can. Wrap one more layer of duck tape around the Pringle's piece and some of the exposed Flare to hold them together. Try not to put any duck tape on the actual rim of the Flare. Cut some back if necessary.
Cut four vertical slits down the sides of the Pringle's can. Not all the way down, just to the point where the flare is inside the shell. Flex these flaps out once and then back to their regular position.
Insert one balloon. It should not project out further than the front edge of the Pringle's can, if it does, you are using too large a warhead.
Finished shell without warhead.
Finished Shell with warhead.
When the round is slid down the barrel, the sides of the nose will be pushed together by the inside of the barrel and the balloon will be held between them. When the launcher is fired, the round flies out at maximum possible speed, due to the air-tight, but low friction Flare. As it hits still air outside the barrel, the cut sections on the Body deploy, releasing the balloon to continue on its flight without slowing. While the fins of the can, catch air like a drag chute and cause the shell to drop to the ground fairly close to the launch-site.
This shell has the highest air-efficiency level I've ever seen, while at the same time staying cheap and easy to use. The more efficient a shell is, the farther it will be able to send a balloon with the same amount of air-power.
The previous champion for air-efficient WB-Shells in my opinion had been DX's design, a Pringles can wrapped in several layers of duck tape. Which I had noticed tended to cause a significant amount of friction inside the barrel. And so, after a lot of work, I've built my own low friction but air-tight design. The Pringle's can DOES make up a portion of the shell, but it is only being used to hold the balloon and prevent rupture or friction.
After performing many tests, I have found that the Snake-Eye has the Pringle's method beat on several accounts:
It has approximately 15% higher efficiency.
About two shells can be made out of a Pringle's can, instead of just one.
Balloons are less likely to detonate inside the barrel when firing.
The Snake-Eye has a lower drop-off distance. (Making retrieval faster.)
They weigh less and do not include any metal parts, such as the Pringle's metal bottom.
(Which could be potentially painful if struck at close-range.)
It is shorter in length, making it easier to transport and takes up less space in the barrel.
(This is also highly relevant for one of my more important "Coming soon" items)
The only problems I've found with the V7 Snake-Eye is that it is so air tight that the pressure behind it builds up and makes it difficult to push down the barrel. This however can be solved by either cutting a small notch in the flare, or by installing my (***CLASSIFIED***) piece that will soon be unveiled.
The other slight issue (though the Pringle's method has this too) is that the body can become somewhat soggy if it gets wet. I've searched for an alternate, water-proof body, but with little success. If people here have any ideas, please post them. The piece must be cylindrical, at-least 4 to 5 inches long, fit down a 3-inch barrel without TOO much room between it and the walls and needs to be able to flex.
