Gunpowder shells

Defense Gunpowder, shells, rocket fuels, atomic weapons... 

Initially the main piped match fuse is lit and a fraction of a second later the flame from this fuse reaches the gunpowder lift charge in the bag at the base of the shell. 

The gunpowder explodes in a further fraction of a second, the explosion blowing the shell out of the mortar tube in the manner of a shot from a cannon. At the same time a return section of piped match is lit by the explosion, transferring flame back to the top compartment where it reaches the quickmatch placed across the head of the 25 mm pressed delay fuse. 

The gunpowder lifting charge beneath a shell provides a source of chemical energy, a proportion of which, depending on the efficiency of the mortar, is converted into kinetic energy in the shell. 

However, in practice, the energy of the hot combustion products of the gunpowder is never fully utilised in providing forward motion to the shell. Losses occur unavoidably in several ways - as radiation as residual energy of motion of the partially expanded gases as leakage of gas around the shell and as wave motion (noise) in the surrounding atmosphere. 

AFTERGLOW The glowing remains produced by the firing of gunpowder-based products such as quickmatch. It is very important that any afterglow is extinguished, especially when reloading shells or mines into mortar tubes. 

Ammonium picrate [also known as Explosive D Structure (2.9)] was used as a military explosive to fill armor-piercing shells because of its relative insensitiveness to impact It was also used in admixture with KN03 as a substitute for black powder or gunpowder. Ammonium picrate in conjunction with TNT [Picratol-52/48 (Ammonium picrate/TNT)] was also formulated and used. 

Smoke shells and rockets are used to produce smoke clouds for military signaling and, in daylight fireworks, for ornamental effects. The shell case or rocket head is filled with a fine powder of the desired color, which powdered material need not necessarily be one which will tolerate heat, and this is dispersed in the form of a colored cloud by the explosion of a small bag of gunpowder placed as near to its center as may be. Artificial vermilion (red), ultramarine (blue), Paris green, chrome yellow, chalk, and ivory black are among the materials which have been used, but almost any material which has a bright color when powdered and which does not cake together may be employed. 

Firecrackers have been around for at least a thousand years. The first firecrackers, believed to have been developed by the ancient Chinese, were made up of black powder (also called gunpowder), stuffed into bamboo tubes and tossed into a fire where they made a loud pop. Today, gunpowder is stuffed into a cardboard tube and a fuse is used to light the black powder. Italian firemasters are credited with inventing the shells that allow aerial fireworks to be launched into the air and explode in a shower of color. 

Gunpowder for fireworks is used in two forms, meal powder and grain powder. Meal powder is a fine black dust and is employed In all cases of mixing. Grain powder is of three kinds, F, FF, and FFF—fine, double fine and treble fine. FFF is best for crackers, simply tiecause it runs rapidly down the pipes for driving stars, shells, etc, F will be sufficient... 

These ere usuelly mede by filling the eb eeee with e finely divided powder of the desired color cloud to be obtained. To the end of the shell fuee ie ettached a small bag of gunpowder which should be located as near the center of the shell ee possible. Thie. when exploding serves to scatter the colored matter end produce the cloud. The errengement of the lute mey be used es shown in Fig. 67<... 

They had never bothered to ponder the inconvenient fact, for instance, that the gunpowder propelling every bullet and the explosive charge inside every cannon shell were made from nitric acid, and that nitric acid was manufactured from nitrate that arrived on ships from Chile. The fragile supply lines across the Atlantic now were blocked by British warships. 

Iron has also played an important role in warfare and weaponry. Beginning in the Iron Age, around 1100 b.c., warriors began to use iron swords. These powerful swords vanquished many opponents and were the weapon of choice for more than 2,000 years. Later in history, iron also played a role in the production of gunpowder, cannonballs, gun shells, and bullets. 

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