Ed,
Only a little bit. The Snowmass, CO. 60+ inch diameter
fireworks (2 tries in 2 years) from a couple of years ago
was probably at least partially recycled ignition patches.
We sat around a bucket, drinking beer, and cutting open
patches of powder for use in it. (Once !)
I was only really involved in checking some math on the
mortar accelerations and why the first one just exploded.
Those guys did really good work, Bad luck with an injury was
probably the cause of the failure. When someone gets hurt,
even from slipping in the snow, Everyone else needs to stop
and recheck everything they are doing. No injuries from the
failure itself (except pride).
-Gar.
From: Dr Edward Jones <RocketPioneer@xxxxxxxxx>
Date: Sun, 3 Jan 2021 19:03:55 -0700
Subject: [AR] NC solid propellants and amateurs?
My earliest days of hands-on amateur rocketry were in 1951 or
thereabouts, when a man in Kansas was purveying bags of smokeless
powder, war surplus and salvaged, as it were. He ran ads in American
Rifleman, offering various grades from fast-burning small bore to
grains of powder for the 16-inch naval cannons. I chose the naval
cannon grade, which he sold for about a dollar a pound plus postage,
and our postmen were happy to deliver to our rural mailbox.
That stuff was in hard pellets, perforated with about six tiny holes,
about 1/2" dia and and inch long, black and shiny with fine graphite.
It burned slowly in open air, so it was easy to ignite a grain and
toss it from the fingers.
The other type he sent as about 1/4" dia by 5/8" long single
perforation. Both seemed to have a modest burn rate, and left neither
smoke nor ash. Fun stuff launched from a slingshot. And those
propellants led to amateur rocketry.
In my youth, among my very youthful colleagues, we chose to use
Bernzomatic propane cylinders, properly flushed and refitted with a
substantial nozzle. This was before a cousin brought us an inert 3.5"
bazooka training round from nearby Fort Ord.
Bernzomatic rockets launch from a trough beside Salinas River mouth
were spectacular. We imagined we were "with" the fellows at ARS and
USRS. We were around eleven.
So the bazooka round, loaded with 16" gun smokeless grains, was a
successful single launch. Alas we were unable to track the last
half-mile or so of the flight by naked eye. And the rocket remains
unfound to this day, maybe.
NOTS China Lake did a lot of smokeless rocketry including extrusions
on-site in the late 1940s, IIRC.
Have any amateurs experimented with NC solid propellants?
Edward,
Fan of all things nitrated