Tag Archives: Biggest Firework Shell


Every year, across Japan there are literally hundreds of Firework Festivals. Japan has a 400-year history of firework production and they mainly create firework shells of differing sizes. Annually, the small town of Katakai plays host to thousands of firework enthusiasts of all ages to watch first hand the Hanabi Takai Festival. This event usually lasts around 2-3 hours during which time hundreds of shells are fired from mortar tubes which are everything from 6 inches in diameter to the HUGE 4-foot ones used for the spectacular Yonshakudama.

This big bad boy is an incredible 420 kilograms (925 lb) in weight and is loaded into the mortar tube (which to be fair is the diameter of a tunnel) by crane to avoid impact damage and of course because it weighs so much.

Thousands descend on Katakai by coach and train to see first-hand the giant fireworks which are held in the highest regard by the Japanese who believe that the launch will lift the spirits and that the precision of the bloom, shows the skills of the firework artist.

In Japan, like the rest of the World are specially trained to handle the explosives and create some incredible bloom effects. Traditional shell production is taught ‘hands-on’, as skills are passed through the generations pertaining to the sheer intricacy of their creation. The mega Yonshakudama takes up to a year to make as they are ridiculously time-consuming to create.

Here is the inside of a firework shell where you can see all the composite stars, how they are laid out within the shell to ensure that they explode in a certain way.

Anatomy of pyrotechnics

The mega shell is 64 times more powerful than the usual 4/6 inch ones we see over here in the UK. All pyro-makers in Japan consider themselves artists.

The programme for the event is every bit as big as the event and usually is the size of a broadsheet newspaper, packed with details of the shells, their production, sponsors and messages of love and support.

During the event, which is quite lengthy, the locals will pop along to The Shrine to enjoy food from the huge array of concession stands about and treat themselves to a selection of sweet or savory dishes available.

OKOBO MIYAKI – Japanese savoury pancakes filled with shredded cabbage, shrimp, garlic, chilli and noodles topped with a couple of slices of bacon and a fried egg.

YAKI IMO – Basically, a sweet baked potato – a little like our traditional jacket spud man.

IMAGAWAYAKI – A thick pancake with either a sweet or savoury filling.

The history of fireworks in Japan clearly goes back an awfully long way, indeed the images below were in a book produced in the early 1900s which was part of a catalogue of shells which were available.

Here is the supberb video of the Yonshakudama:


Latest News on the Worlds Biggest Shell Launch Attempt

You may recall in early March that Epic brought you news of a forthcoming World Record breaking attempt at creating and firing the Worlds Largest Shell burst.

The current holder is from Japan and the shell was the Yon-Shaku Dama of Katakai Japan where they fired a 120cm diameter shell which weighed in at 420kg and it was launched from a 12m long launch tube. All this effort resulted in a massive 800m diameter burst which was absolutely staggering.

The boffins in charge of the new attempt of a shell which will be over 150cm in diameter and will weigh 1700 lb or over 700 kg.

Here is some additional data for you:

• The outer casing of the shell will be approximately 4 inches thick and will be composed mainly of compressed cardboard and wrapped in heavy paper to ensure that the structural integrity of the shell is maintained.

• The break charge will be a ratio of 5:1 black powder which will be used to coat the seed husks but this may alter before the final product is agreed upon.

• The ‘stars’ will be a combination of metal fuelled colours and black powder based stars and comets for a glitter effect and salts and other effects which are to be a surprise.

• The lift charge will be large pellets of Black Powder which will be determined following further experimentation.

• The mortar tube which will house the shell is still in the planning stage at the moment but is likely to be a stationary partially buried concrete reinforced tube.

We will bring you more information as soon as it becomes available.