Artillery shells - Intro
Artillery shells commonly called
Reloadables or
Festival balls are the king of backyard displays. Having a large burst radius and wide a variety of effects makes this device great for any part of the show where additional punctuation is needed.
There is no standard size for Artillery shells but on average they range in size from one and one half inches to two inches, Inch and three quarters being the most common of all.
Artillery shells come in many configurations some of the most common are:
- Ball shells
- Canister Shells
- Multi-break shells (such as peanut shells)
- Mini shells (or midget shells)
Artillery shells are always sold as a kit containing one or more launch tubes (known as a mortar) and usually 6 to 20 shells. Each type of shell offers its own benefits, lets explore the three most common types.
Ball shells consist of a hollow plastic or paper hemisphere body filled with burst powder and stars. Attached to the bottom is a lift cup filled with black powder that generates a large volume of gas propelling the shell out of the mortar and into the air. At the same time this lift charge ignites a fuse that passes fire to the burst charge. An autopsy of a common brand of ball shell finds that the hemisphere is filled three quarters of the way full with stars, then black powder is added to fill the space between the stars. The shell is wrapped with several layers of Kraft paper providing confinement. Ball shells are on average less expensive then other types of Artillery shells. An effect that is almost unique to ball shells is shaped bursts, that is a shell that when it explodes in the air forms a shape with the stars, such as a circle or smiley face. This is done by placing the stars around the perimeter of the hemisphere and the burst in the center; this applies an equal amount of propelling force to all stars pushing them to an equal distance in the same time period. Because pressure confined in a sphere is applied to the walls equally, and therefore the stars equally.
Canister shells consist of a cylindrical body with an external or self contained lift cup. Like the ball shell the body is filled with stars and burst medium. Canister shells usually have a larger internal volume and therefore a larger burst radius. The cylindrical shape also makes it possible to use inserts such as whirlwinds, whistles and serpents. Canister shells also have a larger surface area in contact with the walls of the mortar enabling greater pressure buildup from the lift; this creates a very satisfying thump as the shell leaves the mortar. Audiences have grown accustomed to this sound being followed by a spectacular effect and often feel excitement before the shell reaches apogee.
Multi break shells are a relatively new addition to the class C market. One can think of a multi-break shell as being two or more ball or canister shells stacked one on top of the other with a lift cut attached to the bottom. After the shell lifts from the mortar the shells burst one after the other in quick succession. This happens because the burst charge from the preceding shell ignites the fuse of the shell above it causing a chain reaction. Often the breaks are much smaller than that of single break shells because of laws that govern the total amount of pyrotechnic composition in each artillery shell. The most common type of multi-break shell is a double break ball shell called a peanut shell, named because it looks much like a peanut. In the last few years there has been a race to see what company can create the most breaks in a single shell. At the time of this writing the winner was shogun’s Decimator a one inch wide ten break shell. This type of shell is great for filling the sky during a finale; it multiplies the number of shells that can be fired from a fixed number of mortars filling the sky with colorful breaks.
Continue to selecting artillery shells for my display.Posted to:
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