Big Bertha is the name under which some pieces or families of WW1 artillery cannons were known. It's usually associated exclusively with one specific gun, the Kaiser Wilhelm Geschütz (also known as the Paris Cannon) created to bomb Paris from a safe distance employed by the German army during WW1, although this is not correct, since it was also used to name a model of heavy mortar-like howitzers. The name comes from a descendant of the founder of the Krupp steel and arms manufacturer - Bertha Krupp.

The difference in caliber and performance in the two cases is evident: The Paris Gun or Kaiser Wilhelm Geschütz was a very long cannon piece which:

• Shot 210 mm calibre shells weighing 120 kg each.
• Used 200 kg of propellant explosive charge.
• Had a barrel length of 45 m and weighed 256 tons.
• Had a maximum range of 120 km.

Originally conceived as a naval weapon, the gun was manned by a crew of 80 Kriegsmarine sailors under the command of an admiral, and was surrounded by several batteries of standard army artillery to create a "noise-screen" around the big gun so that it could not be located by French and British spotters. The projectile reached a maximum height of almost 40 km, making it the first man-made object ever to reach the altitude of the stratosphere, thus virtually eliminating drag from air resistance, allowing the shell to reach super-sonic speed and achieve a phenomenal range of over 80 miles. Not until liquid-fuel ballistic missiles were developed 30 years later was this accomplishment equaled and finally surpassed. The shells were propelled at such high velocity that each successive shot wore away a considerable amount of steel from the rifle bore, and each shell was sequentially numbered according to its increasing diameter, and had to be fired in numeric order lest the projectile lodge in the bore and the gun explode. After 20 shots the entire gun barrel had to be removed and replaced with a new one.

The Paris Gun was the largest gun ever built for its time, only to be surpassed in WW2 by machines such as the Schwerer Gustav gun or the V3 complex of Mimoyecques.

The other "Big Bertha" guns were completely different siege mortars. Designed in 1904 and produced by the Krupp factories in 1914,the L/14 model howitzer was a movable 42 cm siege mortar with shells weighing 820 kg each and a maximum range of 15 km, with a maximum elevation grade of 80 degrees. Only 4 of them were built, and were used during the German assault upon Verdun from February 1916, along with other assaults.

In WW2 at least two machines were created re-proposing the concept of the siege mortar: the Sturmtiger and the Mörser Karl .

Links

• http://www.firstworldwar.com/atoz/bigbertha.htm