This chilling video shows just how easy it is to hide an AR-15 and hundreds of rounds of ammunition on your person.

Rob Buck made the 83-second video, which he posted on Facebook on Tuesday with the caption: 'For the conspiracy theorists that say it can't be done.'

In just over a minute, Buck is seen wielding the semi-automatic assault rifle and quickly attaching and removing several high-capacity magazines before pulling out a handgun and doing the same.

The weapons are similar to the ones used by gunman Omar Mateen, who killed 49 people at the Pulse nightclub in the early hours of Sunday morning before he was shot dead by a SWAT team.

This chilling video shows just how easy it is to hide an AR-15 and hundreds of rounds of ammunition on your person

Buck's intention appears to be to show that an AR-15 style rifle be concealed under clothes in public - and that one prepared individual can also carry enough ammunition to commit a massacre.

His video has since gone viral, with 16 million views and more than 200,000 shares.

It starts with him walking around his living room and nothing appears amiss - until he lifts his shirt to reveal he is carrying the large assault rifle. He then pulls it out from inside his jeans.

Although he does not fire either the AR-15 or the handgun, he shows that it only takes seconds to switch out magazines on the rifle and reload the weapon.

The video ends abruptly with Buck mentioning '264 rounds' - apparently the amount of bullets he has loaded into the rifle and handgun.

Rob Buck made the 83-second video, which he posted on Facebook on Tuesday with the caption: 'For the conspiracy theorists that say it can't be done'

Buck's intention appears to be to show that an AR-15 style rifle be concealed quite easily in public - and that one prepared individual can also carry enough ammunition to commit a massacre

Mateen, an American born in New York to Afghan parents, used a Sig Sauer MCX, an assault-style rifle, according to the Washington Post, and a pistol to commit the deadliest mass shooting in American history shortly after pledging allegiance to ISIS.

The 29-year-old, who had purchased the guns legally, was killed after a shootout with police.

Orlando police chief John Mina originally said than an AR-15-type assault rifle had been used.

The Sig Sauer MCX was designed to meet U.S. military requirements for a small, quiet combat rifle for use in close quarters.

The semi-automatic rifle hit the market in 2015 after years of development by the Newington, New Hampshire-based company, which advertises it as an 'innovative weapon system built around a battle-proven core.'

The weapons shown in the video are similar to the ones used by gunman Omar Mateen to kill 49 people at Pulse nightclub in Orlando on Sunday

Gun control advocates say the MCX, which comes with a magazine that carries 30 rounds, is exactly the type of assault weapon that should not be available to civilians.

Its light weight and ability to be fired and reloaded quickly make it an ideal gun to carry out an attack in a crowded place, they say.

'This is a flagrant and grotesque example of how weapons designed for the battlefield are sold to the civilian population in the United States,' said Josh Sugarmann, executive director of the Violence Policy Center, which issued a report on the weapon on Thursday.

He noted the gun features a folding collapsible stock that can make it smaller and a forward handgrip that allows users to repeatedly fire without burning their hands.

He added: 'The reason that shooters use weapons like this is because this is exactly what they were designed for.'