On Sat, 28 Nov 2009 11:45:12 -0500, John Ferrell
wrote:

On Fri, 27 Nov 2009 17:13:50 -0800 (PST), Gary
wrote:

On Nov 27, 11:27?am, John Ferrell wrote:
There is an artical by W4SSY in the March 2009 QST Magazine. I am
planning to duplicate it ...
... snip...
I bought most of the supplies last night at Home Depot. The Orbit
sprinkler valve was only about $12. It is an inline type valve like
the one in the artical. I was thinking I would use a long piece of
pipe as the accumulator but after doing the math I have decided to go
back and get a piece of 3 inch pipe to use. BTW, the cement and primer
is available in a single package for about $6.50. I am a little
concerned about the loose fit of the projectile in the 1-1/2 inch
barrel.

I will report back as I continue.
John Ferrell W8CCW

It is a 1-1/4" X 24" barrel, the projectiles are two 3/4" end caps on
about a 4" scrap of 3/4" PVC....

Test fire at 30 PSI dry.. it huffs and honks!
Next: 35 PSI and projectile nearly straight up... disappointing!
Next: 45 PSI and leaning towards the woods. Still not too impressing.
Next: 52 PSI about 75 degrees toward the woods. Whacked the tree
smartly at bout 60 feet or so...
Next: 55 PSI a little more vertical... overshot the tree with lots of
clearance and passed over several others and rattled down in the
woods. I saw it come down but still lost it in the leaves. It is time
to get the fishing reel in place! The tire pressure gauge I measured
with may not be accurate, it is about 25 years old.

BTW: The Orbit sprinkler valve has a manual switch function that opens
the valve with a quarter twist of the solenoid. It works so well I may
not bother to use the electrical switch. With an air compressor in my
garage it will be a while before I test it with a hand pump!

I believe there are many ways to boost this thing to more power but
keeping the 3X12 tank minimizes the air requirements (pumping) and the
24" barrel is adequate to get the job done. Initial testing leads me
to believe that this device will serve my needs!

John Ferrell W8CCW