On Apr 21, 9:31=A0pm, LadyKate <ladyk...@[EMAIL PROTECTED]
> wrote:
> On Apr 21, 6:23=A0pm, Mike Burge <frontier_market...@[EMAIL PROTECTED]
> wrote:
>
>
>
>
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> > On Apr 21, 8:16=A0am, Auriga <brada...@[EMAIL PROTECTED]
> wrote:
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> > > With no catalyst it is a rather slow burning mix. =A0In a 3/8 di.
tube=
> > > you get about a 3 sec. whistle, which is used for inserts.
> > > I certainly don't advocate doing this, especially with rockets or
when=
> > > using catalysts. =A0But when you are making a bunch of inserts with
a
> > > relatively safe comp it is a much faster alternative.
>
> > > On Apr 21, 5:07=A0am, Bonedaddio <l...@[EMAIL PROTECTED]
> wrote:
>
> > > > On Apr 21, 12:49=A0am, Auriga <brada...@[EMAIL PROTECTED]
> wrote:
>
> > > > > Although most say you should always press whistles as opposed to
> > > > > ramming them there are instances where a rod and mallett are
bette=
r
> > > > > suited. =A0I was usind a 70/30 perc salicylate mix in 3/8 tubes.
=
=A0With
> > > > > little more than a tsp. of comp and proper safety gear I felt
that=
> > > > > pressing would be too time consuming. =A0With some friction and
im=
pact
> > > > > tests ramming was commenced. =A0No problems.
>
> > > > Seems to me that's a mighty brief whistle?? I'm =A0curious about
the=
> > > > geometry: length of the tube, length of open tube to comp, etc.
>
> > > > Perhaps I'm just being paranoid, but I strongly doubt I'll be
rammin=
g
> > > > whistle mix, unless there is a consensus of the people on this
> > > > newsgroup that I respect saying it's OK. I've had no accidents in
tw=
o
> > > > years of this hobby, and all my fingers, eyes, skin, etc. I vote
for=
> > > > keeping it that way!
>
> > > > Les- Hide quoted text -
>
> > > - Show quoted text -
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> > if its relatively slow burning and you are using small amounts
> > perhaps. I have been studying the70/30 loose using perchlorate/
> > benzoate and its some powerful stuff, but your using a different mix,
> > so if you take proper precaution.. ok, but I would never do that for
> > large rockets like you stated, especially with fast whistle, bc if it
> > goes off you wont be able to tell the difference between flash powder
> > beyond light output.. Its not like your ramming lead styphnate or
> > mercury fulminate but its still a sensitive mixture.- Hide quoted text
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> > - Show quoted text -
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> I have found that pressing whistle inserts in an arbor press is just
> as fast as tamping and I can include metals that would normally
> sensitize the whistle to where tamping it would be dangerous.
>
> Todays typical whistle mix isn't very sensitive but there are so many
> variations that ARE sensitive - and whistle is so darned energetic -
> that I like to play it safe and press the stuff. It depends so much on
> what the whistle is made of. For instance, some of the older picrate
> and especially the gallic acid mixes are especially sensitive to both
> friction and impact when compared to today's formulas. See ****mizu
> FAST page 232 for a relative *****sment of this.
>
> Potassium perchlorate whistle may burn vigorously and explode if even
> slightly confined or self-confine if in 100 grams or bigger piles.
> However, it is not very sensitive to impact or even friction.
>
> We have hit bags of whistle with 223 and hotter rifle rounds and the
> only thing we got were holes in the bags and whistle mix dispersed on
> the ground.
>
> Take a BB-size bit of your *pure* whistle mix, with a catalyst or
> without, and try to get it to pop by hitting it or even rubbing it
> with a hammer. =A0It probably won't happen if you are using potassium
> perchlorate and salicylate or benzoates - and no metals.
>
> Many things DO sensitize today's whistles. A small addition of Ti, Mg,
> MgAl, Al or any of the common, finer, pyro metals and some non-metals
> (see ****mizu FAST again, page 319) =A0will make a bag of whistle that
> wouldn't explode if run over by a truck into a nifty exploding target.
> Which makes generalizing that whistle isn't sensitive a real problem
> because someone will hear what they want to hear and start tamping a
> whistle rocket that has a bunch of sponge Ti in it... bada booooomm.-
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> - Show quoted text -
I don't disagree with anything you said but I did get a bag of
perchlorate whistle to go off at 50 yards with a 300 winchester magnum
nosler partition :) but I did have Ti. in it for effect, so you are
right it is relatively safe left as is, but its quite energetic, I mix
mine very well, so i can't really tell the difference between the burn
rate of my 70/30 whistle and my 70/30 flash was in not for the bright
light output of the flash. They both pop between a layer of masking
tape.
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