I think most of those are technically “double base” and DB or not they can
detonate under some circumstances. And then ATF regulation raises its
displeasing head...
Recall that ammonium perchlorate composite propellant was effectively banned
for a time. This might require an explosives manufacturer permit and user
permits.
Ultimately DB propellant isn’t much better at its best than APCP, and even
adding detonatable energetic materials like RDX only shows 2-4% better Isp than
straight DB and APCP. Practically the only justifications are smoke exhaust
less tactical missiles and volume constrained SLBM systems.
-george
Sent from my iPhone
On Jan 3, 2021, at 6:04 PM, Dr Edward Jones <RocketPioneer@xxxxxxxxx> wrote:
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