Supergun

A supergun is an extraordinarily large artillery piece. This size may be due to a large bore, barrel length, or a combination of the two. While early examples tended to have a fairly short range, more recent examples have sometimes had an extremely high muzzle velocity, resulting in a very long range.

Depending on the design, they may be used to destroy heavy fortifications or bombard an enemy from extremely long range.

In the context of late medieval siege warfare the term superguns is sometimes applied to stone-firing bombards with a ball diameter of more than 50 cm. These superguns were either manufactured by forging together longitudinal iron bars, held in place by iron rings, or cast in bronze with techniques generally similar to bellfounding. Known examples include the Pumhart von Steyr, Dulle Griet and Mons Meg (all iron) as well as the cast-bronze Faule Mette, Faule Grete and Dardanelles Gun.

At the beginning of the development of superguns was the desire to increase the effect of the projectiles. To this end, master gunners first simply used larger powder loads. These, however, exerted larger pressure on the existing cannon and could make it burst, causing the death of the irreplaceable gunner with his crew (and even kings). In addition, it was observed that, due to their higher velocity, stone balls were shattered by the impact on the walls rather than smashing them. Thus, the mass of the cannonballs and, consequently, of the ordnance, also, continually increased, culminating in giant cannon like the Pumhart von Steyr which fired a 690 kg ball. Apart from the anticipated improvement in penetrating power, other factors such as prestige and a potential deterrent effect also played an important role.

For all their manufacturing quality the superguns were only moderately successful. Their military effectiveness turned out to be disproportionate to their overwhelming logistical demands and financial costs. For the cost of a single supergun, two or three large bombards with a reasonably smaller caliber (in German Hauptbüchse) could be produced whose firepower was enough to shatter any medieval wall, in particular when it was concentrated in a battery. Due to their less bulky dimensions and higher rate of fire, these artillery pieces could be more flexibly deployed and caused more destruction in any given length of time. Furthermore, the transition from stone to smaller, but much more devastating iron balls meant that super-sized bores became unnecessary. The caliber of a 50 pound ball, for example, could be reduced from 28 to 18 cm when using an iron projectile instead.

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