It is probably the largest cannon in the world
The Jagadamba Bhavani Tope (cannon) located at the highest burz of historic Koulas Fort called the Raja Kunwar Padam Singh Gaur burz at Koulas village of Jukkal mandal in the district is probably the largest cannon not only in India but also in the world.
The cannon, which is 23 feet in length and weighs 70 tonnes, is made of iron and other alloys and is larger than that of Jaivana tope (20 feet length and 50 tonnes) on Jaipur fort and one on the Bijapur fort (15 ft and 55 tonnes) which were earlier considered the bigger cannons in India. The Jagadamba Bhavani tope has a caliber of 16’’ and explosive head of 150 kgs whereas its rival topes have 11 inches and 18 inches and 100 kg explosive heads respectively.
Statistics above reveal that the Jagadamba Bhavani cannon is undoubtedly the largest and deadliest cannon in the world. This is a rare example of technology and metallurgy which was unknown to mankind in 1725 AD when it was set up on the fort. It sounds like a bell when hit by a hard object and has two parts -- cannon and primer.
Explaining the significance of the cannon, Col. Ajith Kumar Singh Gaur, the great grandson of Raja Padam Singh and an expert in guns in the Indian Army, said that eight elephants and a few hundred men were pressed into service to take and place it on the burz in those days.
Iron and stone balls were used as projectiles. First, iron and stone balls were put inside the cannon and then 150 kg gun powder was stuffed in it and primer. The primer was lit by a wick and the firer used to jump into a big water tank built next to the cannon to save himself from sounds, burns and concussion effect. It was tested few times and declared battleworthy, says Mr. Singh, who has a doctorate in metallurgy and teaches the subject in defence.
Performing puja, a couple of days ago to the cannon, as has been their family tradition, on the fort, which was 150 kilometres away from Hyderabad city on the Hyderabad-Nanded road, he said because of the cannon set up with the blessings of Goddess Bhavani, no enemy dared to attack the fort in the last three centuries.
The fort was occupied by the brave Rajput king Raja Kunwar Gopal Singh Gaur in 1724 AD.
He was the associate of the Asaf Zah-I (first Nizam). The Nizam granted him Koulas, Khandar and few parts in Maharashtra for his bravery in the battle of Balapur and Shakkar Kheda. Raja Gopal Singh renovated the fort and built the Jagadamba Bhavani temple on the fort which is some 400 ft high.