One of the most interesting hand firing operations I ever seen is the tradicional Japanese quick firing method of aerial shells!
Essentialy, it consists of a special made shell wich has the lifting charge attached and enveloped with a thin kind of Japanese tissue paper usually named "Kozo", made from vegetable fibers, a handle attached to the top of the shell (so the pyrotechnician could hold it), a metal mortar and a hot iron piece (may be a chain or a spiral).
In the image below, you can see the shell components and the ignition metal:
Image from the book - Fireworks - The Art, Science and Technique by Takeo Shimizu
The firing procedure is simple: First, the metal piece is heated in a furnace or a bonfire until it turns incandescent and put inside, at the bottom of the mortar. Next, the operator takes a shell and drops it inside the mortar. When the lifting charge contacts the hot glowing metal it explodes.
Image from the book - Fireworks - The Art, Science and Technique by Takeo Shimizu
In this kind of shooting, the mortar is a bit wider than mortars used in other kinds of firing to prevent the shells to stick in the walls during the shell dropping.
Usually, each mortar could fire about 10 shots with a single "hot iron".
Even thought it's dangerous, this technique is widely used in Japan nowadays and in my personal opinion is one of the most wonderful and exciting techniques I ever seen.
You can see a video of the entire firing operations here:
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