this is an easy way to make a collapsible blow gun in about 5 minutes with of the shelve parts from you local hardware store.

great for hunting, target shooting, survival, camping, ultra light weight and wont go rusting like my old curtain rod

the only thing only cost about 10 dollars

warning: blow guns are dangerous never point them at some one or something to do not with a seriously hurt or potentially kill, i take no responsibility if you get you or someone else hurt

Step 1: Parts

head to your local hard wear store and check out the poly pipe.
15 mm is a good diameter, its not to large that your run out of puff

you will need:
      2x 15mmx750mm poly riser
      1x 15mm threaded coupling
      1x 15mm -> 20mm reducing bush
      1 x 25 mm threaded coupling
optional:
      super glue
      hack saw
      knerf bullets

Step 2: Assemble

putting it all together is pretty simple,
25mm coupling -> reducing bush -> 750mm riser -> 15mm coupling -> 750mm riser

Step 3: Ammo

ammo:
of course it will take the standard skewer and paper cone or traditional fluff thistle and even the crazy exploding cones
but it is also the right diameter for nerf darts for when your feeling like some fun and dont what to kill any thing
it fires them faster hard and more accurately then any gun mod ive ever seen

Step 4: Optionals

optional steps:
super glue - a few drops of super glue on one of the threads middle threads helps with assembling
thread removal - I also loped off the end thread that wasn't needed, you could however live it on if you wanted a third length of riser, or maybe a silencer... food for thought

I'm search there's plenty more you can work with I'd love to hear back with any idea you have