It isn’t just the USA that’s turned away from the 1970s-vintage SS109 round (which is what our 62-grain M855 was, essentially) in pursuit of more accurate ammunition with improved terminal ballistics. The UK has done so, also, although they’ve gone in a different direction from the US.
BAE Radway Green, the Britsh military ammo monopoly contractor, has also improved the venerable 7.62mm round. The British tech ‘zine The Register visited Radway Green and has a rundown on the new ammo — heavy on The Reg’s patented juvie snark, but well-stuffed with technical details.
What’s changed? … It’s all down to penetration – or punching the same depth of hole in ever-better-protected targets.
While RG’s existing products, the 7.62mm L44A1 and the 5.56mm L17A2 cartridges, did that more than well enough when they were originally specified by the Ministry of Defence, modern battlefield technology and techniques mean the military are looking for something with a bit more oompf to fire down their rifles and machine guns.
RG has swapped all-lead bullets for steel in pursuit of better penetration against hard targets – though there’s a lot more to it below the surface.
The two new designs of cartridge, known as the Enhanced Performance (EP) round in 5.56mm and the High Performance (HP) round in 7.62mm, feature new – and, in the HP’s case, heavier – bullets. In addition, the HP round switches from single-base propellant powder to double-base, to give the heavier bullet the same flight characteristics as the old one. The EP also discards the age-old NATO SS109 bullet design, which incorporates a steel tip in front of a lead core, for an all-steel bullet, cased in the same gilding metal jacket as before. Its profile is similar, though.
The genesis for this seems to be the same as that for the US Army and USMC’s newer rounds — technology made better ammo possible. Unlike the Americans, though, the British Army didn’t have to sell the ammo as a “green” boondoggle to social-engineering obsessed Ministry of Defence.
Simon Parker, a project manager at BAE Systems Radway Green, spoke to The Register about the new rounds and the decisions behind the changes in their makeup.
“We wanted to see if we could improve performance against hardened targets. Having a solid hardened steel core improves performance above that of the steel tipped round,” he said. The new 5.56mm round, which will be known as the L31A1 in British service, retains a bullet weight of 62 grains (4g), meaning its ballistic performance will be very similar – an important similarity for soldiers firing it down their SA80 rifles.
For the 7.62mm round, known as the L59A1 in British service, the biggest change is to the weight of the bullet, from 144 grains (9.3g) to 155gr (10g). This increased maximum weight allows the new bullet to incorporate a steel tip, similar to the 5.56mm NATO SS109 design, giving it more mass with which to punch through a light target. Graphs from BAE claim that the HP bullet can penetrate an 8mm steel sheet out to about 400m, whereas its predecessor could only manage it at half that distance.
“We have a standard ball round which is 144gr and a sniper round which is 155gr. The sniper round is manufactured under tighter tolerances and conditions. The 7.62mm High Performance round is not quite the same as the sniper [round] but it’s considerably improved over the standard 144gr bullet,” said Parker.
The propellant in the new 7.62mm round is the same as the 155gr L42A3 sniper rifle round, which is continuing in production. It is a double base propellant – so why the change from single base?
“It’s merely because it’s heavier,” said Parker. “Moving from the 144gr to the 155gr means you need a bit more energy in the propellant. We already use the double base propellant in the sniper round so it’s the same propellant as is used in the sniper round.”
It’s interesting to note that the 5.56 round is Boxer primed, and the 7.62 Berdan primed.
Yeah, but how does it work in the real world? Does it pop hadjis?
“The old Green Spot was just the best lot of ammunition that we manufactured, taken off and marked as Green Spot… but 7.62mm HP would outperform Green Spot,” said Parker.
“We’ve not designed it for a sniper rifle application – though the Special Forces use it as such and that’s fine – but it has been adopted in the sharpshooter rifle [the Army’s L129A1]. It was purchased as a UOR and subsequently adopted. We recommended the use of 7.62mm HP and the user really loves it. But it was originally designed, truth be told, for improved target performance through any weapon system. We made it and designed it so it can be functioned through the GPMG and it’s also being used by the Royal Navy in their Miniguns for defence of ships.”
Do Read The Whole Thing™. The section on the environmental testing that the ammunition endured on its way to acceptance — and that samples must continue to endure — is quite illuminating all on its own.
For more information, BAE Systems has a page on the new ammo, with a rather cool video we were unable to figure out how to embed — so go there to watch it. The ammo has been in production for the UK MOD since 2015, but is now being offered to other military forces.