DAN wrote in news:7m16icdpqg5khs1liubis349j9n16t5sjv@
4ax.com:

wrote:

Is there any benefit to this design?

Yes: the venturi tube effect.
https://en.wikipedia.org/wiki/Venturi_effect


ever make a beer or coke can tubi ?

cut the top out of a can, then cut the can around the waist
about half way. make it a good clean cut, and make sure you retain the
round shape.

throw the can end first with twist as if you were throwing a football in a
spiral pass. you'll be surprised how well it can fly if you throw it
right. worked much better with the older steel cans, but it can still
fly with the aluminium.