JP> Interesting post, thanks!
I do my best .
-> You have High Explosive (HE) which can be fused so it;
-> A) TIMED, explodes before impact (good for spraying
JP> Are these three DIFFERENT shells or is there a way to set
JP> the same shell for Timed, Quick, or Delayed?  If so, must be
JP> a pretty neat fuse. 
I'm not an artillery man so most of my technical info
is "book learning" or second hand so some of my answers
may be vague or off a little but here goes. 
The HE shell is just a chunk of steel packed with TNT,
I think they still use TNT.  To make it go boom you
need a detonator/blasting cap which is combined with a
fuse.
For QUICK or DELAYED you use the same fuse.  To set the
delay you just screw or unscrew the top of the fuse.
The fuse can be set to go off as soon as it hit
something, like a rifle round primer, to a couple of
seconds.  There are fuses that can be set for a really
long delay, a couple of minutes or hours I think.
The TIMED fuse, which probably isn't used much any
more, is a different critter.  It was activated by the
acceleration of the shell at firing and went off a set
time after that.  There was a table you used to set the
time based on range and how high you wanted the shell
to burst.  As I said this is obsolete with because of
proximity fuses.
JP> How long would it take to set the amount of time on each
JP> Timed shell? Ie: Would calling for Timed slow down the
JP> response time and rate of fire?
Not long, only a couple of seconds.  Defiantly less
then it takes to load a round.
-> White Phosphorus (aka; WP, Willie Pete, Willie Peter).
-> WP burns on contact with air (oxygen technically).
-> It's usually used as a spotting round but it can be
-> used as a incendiary round.  Nasty stuff!
JP> I thought smoke rounds were used for spotting?  I would
No.  A smoke round would hide the target and would be
useless at night.  The WP round smokes enough for you
to see it but doesn't hid the target
JP> think that the disadvantage of using WP is that your
JP> spotting rounds are the ones MOST likely to cause a
JP> "friendly fire" incident, no?
Not really.  Most of the time you just use the HE
rounds for spotting.  You can see where they hit and
adjust from there.  Very few of your arty "friendly
fire" incidents come from spotting rounds.  Most of the
time it's because either unit A calls fire on unit B or
someone goofs up the coordinates (that could be the FO
or fire control).  On an FTX one time I had a guy get
confused and he gave OUR grid coordinates to fire
control instead of the target's.  Luckily it wasn't a
live fire exercise.
                      Remember:  Freedom isn't Free!
--- timEd-B11
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