Potatos are the best and the original!
These FREE pool water tesster bottles work PERFECTLY in 2" chambers. These are from Pinch-A-Penny so if you know of one where you live, just ask 'em for a free water tester bottle!! Works great if you fill it with water too.
Any kind of caulk gun things work great in 2" barrels! I picked these up at a construction site. Another freebe!
These were some spent fireworks from this last 4th o' July. They work pretty good for 2" barrles but are kinda light.
Wine bottles are AWESOME!! Just gotta find the right bottle for your gun. I use these in the 01 model which has a 3" dia. barrel. Just put a little tape (clear packing tape is best, less friction) on the end and let 'er rip! Fill em up with water too, very cool. They also can be used over and over again of they don't break, but don't worry, they are stong! Take a look at the videos!
Water works great in pnuematic guns. Just be sure not to fill it all the way up because it might be too much to push out of the barrel and explode on ya, not good. Use a few cups or whatever.
Golf balls are awesome and go really far. If you have a 2" dia. barrel, just put a chunk of potato in first and drop the golf ball in on top of it. Works pretty well. Just be careful, they bounce really good and could poke an eye out!!
Powerade bottle also fit very well in 3" dia. barrels. Just put some tape on the bottle to make a tight seal. We filled this one up with rocks, gave quite a nice kick!