SpudFiles

Last night i was using my 2' cannon to launch 2x2s, for a tight seal with the barrel i used a
2 1/8" holes saw to cut holes in an old computer case. the remaining plastic disks fit well in the 2" pvc. This could be used to cut plugs from other materials as well to lancch projectiles smaller than the barrel itself.

Last night i was using my 2' cannon to launch 2x2s

I assume you mean your 2" cannon?
I'm kinda confused as to what you are explaining though...

yeah 2"
the disks from the middle of the holes saw, left when cutting holes in a material fit in the 2" pipe

Do you mean as a sabot-type object to seal behind the projectile, or as a burst disc?

Still, don't really get ya, got any pics? What kind of saw are you using?

I don't see what's so hard to understand. He was using a 2.125" diameter hole saw, a type of drill bit to cut large holes. Since the outside diameter of the hole saw is 2.125", the inside diameter is the same as the inside diameter of 2" schedule 40 pipe. He was using the pieces he cut as sabots for a square projectile. Understand now?

Good find, although it's already been used. For example, MrCrowley's VAL...
He used a hole saw to make the piston. So the only thing I haven't seen is is them used as a sabot...

OOOOOOOOHHHHHH. I understand now!! I looked up what I hole saw is. I gotcha now, I just didn't know what a hole saw was...now I understand. Good Idea!