The elite troops are also getting an arsenal of new weapons, tried and tested by US special forces.
Lethal bullets designed to “drop” jihadis on the spot will be issued in the next few weeks.
One type of ammunition – the Rapidly Invasive Projectile, or RIP – is designed to cause the maximum internal damage to a target.
The bullet, described as the most lethal ever made, is made by US company G2 Research.
It is designed to splinter into eight pieces, each causing as much damage as a single ordinary round.
The manufacturers’ website states: “It is capable of going through barriers such as sheet rock, plywood, sheet metal or glass and still performs its original intent. The bullet shreds through solid objects and, only then, expends its energy.”
One intelligence source said: “We need bullets with stopping power.
They don’t always have to be high-powered.
“The 5.56mm round issued to the Army will pass straight through a body but won’t necessarily drop a target. There were cases in Afghanistan where soldiers had to shoot the Taliban two or three times before they went down.
“A lot of damage can be done in those few seconds. Expanding bullets are very unpleasant – they produce a massive hole – but will stop a target in its tracks.”
The bullets also reduce the risk of ricochets striking innocent bystanders or hostages as the body takes the brunt of the impact.
G2R officials said they have tested the bullets in a range of automatic and semiautomatic weapons, as well as in rifles, with a 100% success rate.
British special forces will also be equipped with “hollow point” rounds which work in a similar way to the RIP.
Instead of splintering, the bullet tip flattens out and produces a massive wound. The SAS counter-terrorist team will use the bullets in their new HK MP7a1 sub-machines – the weapon used by members of the US Navy’s Seal Team 6 to kill Osama bin Laden.
It is regarded as the best close-quarters submachine gun in the world and is described as the perfect counterterrorist tool.
It is small enough to be hidden beneath clothing but has a rate of fire of 950 rounds per minute and weighs just 2.65lbs.