Step 3: Barrel Assembly
The basic barrel is made up of five lengths of 1 1/4" PVC pipe held in place on one end by a 4" PVC pipe joiner and on the other by a 4" to 3" PVC couple.
Although the gun in game actually has six barrels five was the only way I could get it to work with the real world limitation of available parts. As you can see in the picture five 1 1/4" pipes fit perfectly into a 4" pipe joiner, the next size up (a 6" joiner) had far too much extra room with six 1 1/4" pipes and going larger increased the cost more than I was willing to deal with.
I'm not too concerned about most people's first reactions on seeing it being, "Hey, you only have five barrels!" either, so it should work out fine. If in building your own you find a non-cost prohibitive way to get six barrels to work then congratulations, but if you follow my plan here you'll still end up with a nice looking prop gun.