This is very similar to the ammo I use, with a little fin trimming I can get it to fit perfectly into a 2" barrel

Over the weekend I built a Pneumatic Cannon with hopes of shooting it over 200 yards. My cannon has 2 3"x5' chambers connected via 2 90's and one tee through a 1" ball valve into a 2"x4' barrel. On the end caps of the chambers I have a Schrader valve. My max PSI is 110 due to an old compressor. I fo...