Troops from the Black Watch, 3rd Battalion, the Royal Regiment of Scotland, led a helicopter swoop on a supply route used by the Afghan resistance.
The soldiers from the Inverness-based battalion arrived in Afghanistan at the end of last month and officially became the regional battle group for the south of the country on Friday.
About 200 soldiers set off on a mission just 24 hours later, deploying at dawn on Saturday into Taliban heartland on a gruelling 36-hour operation.
Soldiers from Alpha (Grenadier) Company dropped from helicopters on to a known enemy supply route - and uncovered a stash of lethal explosives.
This included anti-personnel mines, mortars and rocket-propelled grenades, which are the weapons fuelling an insurgency gripping Helmand province and the surrounding areas.
British troops have faced some of their fiercest fighting for years in southern Afghanistan.
The captured weapons were destroyed in a controlled explosion.
Around 30 Afghan National Army soldiers were also involved in the operation, as well as a small number of Canadian and US personnel.
Lieutenant Colonel Stephen Cartwright, commanding officer of the Black Watch, hailed the 'positive result' of the operation.
He said: 'The fact that Alpha Company deployed on operations so soon after their arrival in theatre demonstrates their flexibility and high level of preparation.
'It's pleasing to have had such a positive result.'
Major Matt Munro, commanding officer of Alpha Company, said: 'There is no doubt that our first deployment proved the excellent training that we have been through together.
'The use of helicopters gave us the initiative which we maintained throughout.'
The Black Watch battalion has taken over as the regional battle group from Plymouth-based 42 Commando Royal Marines.