In March of 1988, Bull received a contract to build two full sized 'Project Babylon' 1000 mm superguns and one 'Baby Babylon' 350 mm prototype for a total of $25 million. The project was given the cover designation 'PC-2' (Petrochemical Complex-2). British engineer Christopher Cowley was the project manager.

The Project Babylon gun would have a barrel 156 meters long with a one meter bore. The launch tube would be 30 cm thick at the breech, tapering to 6.5 cm at the exit. Like the V-3 the gun would be built in segments. 26 six-meter-long sections would make up the barrel, totalling 1510 tonnes. Added to this would be four 220 tonne recoil cylinders, and the 165 tonne breech. The recoil force of the gun would be 27,000 tonnes - equivalent to a nuclear bomb and sufficient to register as a major seismic event all around the world. Nine tonnes of special supergun propellant would fire a 600 kg projectile over a range of 1,000 kilometres, or a 2,000 kg rocket-assisted projectile. The 2,000 kg projectile would place a net payload of about 200 kg into orbit at a cost of $ 600 per kg.

In May of 1989 the Baby Babylon was completed at Jabal Hamrayn, 145 km north of Baghdad. The horizontally-mounted gun was 45-m long with a 350 mm barrel, and had a total mass of 102 tonnes. Following tests using lead projectiles the gun was reassembled on a hillside at a 45 degree angle. It was expected to achieve a range of 750 km. An Iraqi defector revealed later that the gun was to be used for several missions:

• Long-range attack using chemical, biological, or nuclear warheads. However since the weapon was fixed, it could only be fired in one direction, and like the V-3 would be easily identified and neutralised by the targeted country. For this reason the Israelis did not consider it much of a threat.

• As an anti-satellite weapon. It would launch a special shell in space that would explode near the target satellite, covering it with sticky material and blinding it.

Production of components for the Babylon gun began in Britain with the knowledge of British and US intelligence services. These were officially 'oil pipeline segments' for the 'PC-2' petrochemical refinery.

On 22 March 1990 Bull was assassinated and the project quickly unravelled. It is commonly thought that he was killed by the Israelis, concerned not so much by the supergun work but rather dynamics research Bull was doing to improve Iraqi ballistic missiles. Three weeks later British Customs seized the final eight sections of the Babylon Gun. On August 2, 1990, Iraq invaded Kuwait, precipitating the Gulf War. This ended Western covert sponsorship of Iraq.

After the war UN teams destroyed the Baby Babylon 350 mm gun, components of the two Project Babylon 1000 mm guns (44 gun sections, four recoil cylinders), and one tonne of supergun propellant (the Iraqis destroyed the remaining 11 tonnes). Only seven slugs for the 350 mm gun were recovered and destroyed. Iraq claimed never to have received any design, assistance, materials or equipment for the planned rocket-assisted projectiles. At the end of September 1995 UNSCOM obtained information on an indigenous 600 mm indigenous Iraqi supergun design - evidence that the project had not died with Bull.