idk much about making them but...
my cousins got inexpensive ones for christmas and boy were they fun!!!

the would easily blow through a free standing 2 liter soda bottle and had a range of maybe 30 yards.
they were very cool.

yours looks like it has the potential to be pretty good, but my little cousins couldn't even cleanly kill a squirrel with his smaller one.(of course he was only 11)
it still sure looks like fun!


slingshots can be fun too, but yeah, def not serious weapons... except maybe three man slinshots... we launched some crazy stuff out of those. <img src="/ubbthreads/images/graemlins/laugh.gif" alt="" /> (flaming snowballs, hunks of metal ect.)

BDB: welcome to the forum. those look like some pretty serious blowguns!
have you taken anything with them??