The yobs - who recorded the disturbing footage on mobile phone and posted it on YouTube - are seen laughing as one screams: "I kill you all!"
The clip, posted by someone with the user name fittysmiffy, takes place in a country road lined with luxury houses.
The 55-second video - said to have been taken in High Wycombe, Bucks - was spotted after YouTube vowed to ban videos featuring weapons.
The Google-owned site introduced the ban for the UK only amid widespread unease about gang violence on Britain's streets.
It said any video clearly "showing weapons with the aim of intimidation" will be taken down, and Home Secretary Jacqui Smith hailed the move as a "real step forward".
However, YouTube has pointed out that the ban is not retrospective, and videos like this one posted prior to the change will only be removed if reported now."
Mark these words; Next up for the shivering Brits is a ban on videos featuring pieces of steel with a sharp edge, lest they scare the ever loving shit out of those who are pretty much afraid of anything and everything that might be used as, or even looks to be, a weapon.