Way back when, magazines like popular mechanics used to advertize blowguns in a tiny little black and white ad near the back of the mag. I think they were called Javalinas or something. Anyway, they were fairly cheap. You had to make your own darts out of long pieces of piano wire, which you had to cut to size, and plastic beads. They included these with the blowgun. They actually drew the aluminium tubing on a slight curve, {to compensate for gravity}, so that when you rotated the tube, you had a perfectly straight barrel. Amazonian natives and such, do the same thing with their carved blowguns. {Didn't know there was this much science to the blowgun did ya?}
There weren't any other manufacturers at that time, I don't think.
So, me and a buddy both got a couple. I think our long ones were 5 or 6ft long. We also got a 3 footer.
Nothing that moved was safe from our darts. These things were deadly accurate! The darts didn't even have cone tips, but would penetrate so far into wood that you needed a pliers to get them out. We even put some through light gauge steel.
They said at the time, that blowguns are the only weapon in the world that people are instinctively accurate with. They were, [and are], right. By their second blow, people are within inches of target, having never used one before. It's pretty interesting.
Of course, the longer the barrel, the more accurate, go figure.
There used to be guys who sold various poisons for the darts through the mail! One fellow advertized cobra venom! The idea was that you could kill anything with a blowgun using poison darts. {Presumeably if it didn't kill you first} The usual trick was to mix your poison with toothpaste, smear it on the tip and let it dry. When you shot at something ,the only thing you had to remember was: DON'T INHALE THE DART!!!!
Ah, those were the days!
Anyway, I don't know if the new two piece ones are any good or not. The darts look a lot better nowadays.
They are a lot of fun.