Uninsured motorist Matthew Saunders was Tasered by police after leading them on a 26 mile night time chase.
Saunders was seen putting on a crash helmet as he sped away from a police patrol who wanted to speak to him about his poor driving.
When the 25-year-old Great Mead, Chippenham, was searched, following the half-hour pursuit, he was found to have a live shotgun cartridge in his pocket Tessa Hingston, prosecuting, told Swindon Crown Court that officers spotted his VW Polo weaving on Devizes Road, in Trowbridge, at 1am on Friday August 24.
She said when they put on their blue lights to stop him, he first put on his hazard lights then was seen waving his hands around inside the car.
"He then reached to the back seat and put on a crash helmet. After that the pursuit began in earnest," she said.
The car went from the A361, on to the A350 towards Warminster where it accelerated to stop officers overtaking so they could lay a stinger device.
Saunders then went the wrong way round a roundabout, exiting on to the A36 towards Bath.
"Officers tried overtaking again and were jockeying for position, at some points on the wrong side of the road and going into a blind bend," she said.
He went at speeds of 80mph in a 60mph zone and the police helicopter also joined the chase as it headed towards the county border.
Avon and Somerset officers managed to lay a stinger across the road but the driver just slowed down and drove across the verge to avoid it.
He then turned into Hantone Hill, a dead end road, where he was forced to stop and was so uncooperative with police they had to use a Taser to subdue him.
As well as the live shot gun cartridge, which he said he was planning to convert into a lighter, he also had an ornamental skull with blades protruding from it.
Saunders pleaded guilty to dangerous driving, no insurance, driving otherwise than in accordance with a licence and possessing a firearm while prohibited.
He pleaded not guilty to possessing an article with a blade or point, and prosecutors accepted his excuse that he was moving house at the time.
The court heard he had a long list of previous offences including getting five years for robbery on 2006, which meant he was not allowed to have the shotgun cartridge.
Mark Ashley, defending, said his client suffered from a borderline personality disorder which meant he was on disability living allowance.
He said he drove away from the police because he knew he shouldn't have been behind the wheel, but was in the process of moving.
Although the driving was bad in parts he said his client slowed down as he went through residential areas and for most of the half hour it was not dangerous.
He said should he be jailed for more than six months then he said he would lose his accommodation.
Recorder Jeremy Wright decided a psychiatric report was needed and adjourned the case to Friday, March 1, with Saunders on bail until then.