What a strange thread. I don't really understand how a fly rod could be
analogous to a rifle barrel, in any sense (except action/re-action). The
comments on the rod forming an arc with the tip following (but not dropping)
makes sense. And...anyone who looks at the physics involved in firing a
bullet i.e. explosion/action/reaction...the force from the explosion pushes
backwards...BUT...the design of the rifle, the way it is held, whether or
not the barrel is ported, are things that are all contributing factors. All
things considered, the shooter and the design of rifles generally tend to
absorb the shock going backwards and also direct it in an upward arc. The
only way I can imagine a rifle barrel dropping is by putting it in some kind
of vise that directs more downward than upward pressure, but that's not how
rifles are held by a shooter nor is it the way rifles are designed (which is
why ports are designed to force gases to exit from the top portion of the
barrel rather that the bottom). I guess, technically, if the barrel was
designed to push backwards with no design to cause it to arc in any
direction...and the barrel was supported in a way that provided no push in
any direction other than directly against the force, the barrel would only
be minimally influenced by gravity and would tend to move in a direction
that is almost totally opposite the force. But, gravity will cause both
bullet and barrel (in a vacuum and with no other considerations) to arc due
to gravity. Depending on the location of the chamber and length of the
barrel, the chamber end would tend to be leading initially, with the barrel
following. With gravity, part of the arc would be with the barrel moving
down initially...but that's not anything that I could see happening in "real
life". My head is starting to hurt...

Obviously, I'm not a Physicist. But....I don't believe the author of the
book is any more of a Physicist either.

I also can't believe I took so much time thinking about this thread LOL

Barry


"Wolfgang" wrote in message
ups.com...

wrote:
On Tue, 07 Nov 2006 10:35:15 -0500, daytripper
wrote:

On Tue, 7 Nov 2006 07:47:36 -0500, "Robert11" wrote:

Hello:

Was reading a book on ballistics the other day, and the author was
describing conditions
where a rifle barrel would drop a small amount as a shell was fired.

He used an example that if one held a fly rod rod truly horiz., and
gave the
handle a very quick
upward (I think he means backwards; toward ones head) pure rotation,
the tip
momentarily goes Downward.

Have my rods away for the season, so can't try it.

Can't visualize this happening.

Does it ?
Why does it, if so ?

B.


I can't see how any downward force vectors at the rod tip increase in
this
scenario, so while he's correct that the rod tip will point below
horizontal,
it doesn't "drop", it simply lags behind the rest of the rod movement,
establishing an arc...

I s'pose the same thing could happen with rifles, to some (hopefully
vanishingly small) degree...

/daytripper

I'd offer that it would be a bit difficult to hold the average fly rod
"truly horizontal"

Well, you'd never know, would you? So, it's close enough.

...unless one just had a lesson or two and the fly rod
in question was the all-new and improved O' Cedar Fishsweeper XLT1000,
for which the instructor was the sole local distributor...

Zzzzzzzzzzzzzzzzzz

OTOH, I'd offer that any rifle barrel that couldn't be held "truly
horizontal" might make a better fly rod than rifle barrel...

Shows what you know. A rifle barrel can't be held truly
horizontal.......EVERYBODY knows that!

And finally, I'd observe that someone who suggests the physics/mechanics
involved in a rifle barrel at the moment of a round's discharge are
generally the same as someone lifting a fly rod would likely not know
much about either...

If anybody ever suggests that, remind us to ask you to remind
us......o.k.? Meanwhile.....amuse us. Tell us what you know about
either.

but on the plus side, they'd be readily recognized
as an expert by some on ROFF...

And thus, YOU must be a recognized expert on SOMETHING!........right?
Hold your breath.

As for the OP's reference to conditions that would cause a rifle barrel
to drop, I'd be interested in learning what those conditions are and
why the author thought that the alleged downward motion of the flyrod
tip was analagous.

Wolfgang