Spider-Man Helix / 4B Shotcannon

 This blaster uses a 4B tank, an extra large tank expansion, a dual action Spalding ball pump and a special inline absolved clip. I imagined this as a versatile, semi auto shotgun. It still needs a little work but is a fun blaster. It loses darts like crazy indoors though!

The internal volume of the tank expansion was sized to the available space in the shell. I added a simple string/spring trigger attached to the 4B's lever along with a spring against the blast valve. It needs re-doing, but I hate triggers and always put them off! I used 3/4" threaded fittings. At the time I only had the male fitting in conduit. I would normally like to use cpvc threaded fittings as they seem more durable and precise.

The barrels are spread horizontally by a piece of thinwall pvc. It gives a much better spread at range.

The performance of this blaster/attachment combo is impressive. It makes quite a sound when fired at high pressures! It was made for .8" darts. It holds 80 at that size and gives 2-3 good shots. It can get darts out to 100' but only at higher pressures. The spread at range is 20-25'. I have a feeling that I can improve the pattern a bit with those rifled, dollar store baton barrels. The pattern starts at about 40' and goes out to 80' with good coverage. Safety is certainly a concern with this much power. I sized things for 1 pump close range shots. With 20+ darts leaving the barrel, the energy each dart has is safe. I would not fire this thing at anyone at close range with a few pumps. The effort involved in getting 100' pressure is quite high. Still I would love to do an adjustable oprv or pressure regulator on this in the future. I would also like to try shmmee's oogoo darts. I plan on separate write-ups on the blaster & attachment,