Snipers are the world's most romanticised killers. Kurt Bayer was granted rare access to New Zealand's deadliest sharpshooters, to watch them in action and find out what makes them tick.
He lies flat on his stomach, camouflaged legs splayed, wriggling deeper into the soil. A leather-gloved finger flutters on the trigger. Faded floppy hat pulled low. The rifle's long black barrel aligns with whispered, staccato instructions from the sniper's spotter, crouched behind him.
In the spotter's high-powered optics, an enemy sentry appears above the compound wall 800 yards (731m) ahead. Seven rugby fields.
After checking charts, doing his own calculations, taking into account wind, altitude, temperature, humidity, the curvature of the earth, and the spinning forces caused by the rotation of the Earth, the spotter calls the shot.
Crack.
With the bullet travelling at three times the speed of sound, the sentry wouldn't have heard a thing before he died.
A blue sky spans the Canterbury Plains, sun glaring off fresh Southern Alps snow. A perfect training day. And a unique one.
The 2nd/1st Battalion Royal New Zealand Infantry Regiment sniper team, based at Burnham Military Camp outside Christchurch, has been joined by New Zealand Special Air Service (NZSAS) comrades and members of the New Zealand Police Special Tactics Group (STG) national sniper team.
The first week is based here on a military shooting range west of Christchurch before another fortnight in the 8000ha alpine winter wilderness of Tekapo Military Training Area.
"It's that train hard, fight easy mentality," says senior constable Tim Carter, STG national sniper team leader.
"We're expected to operate anywhere, any time so we may as well choose to train in the toughest environments. While we perform a different job to the military, a lot the skill sets and methodology crosses over and we take every opportunity to be more proficient in them."
These guys, both police and military, are the elite. Only the best were picked to be here.
The popular sniper selection course is said to have the highest fail rate in the Defence Force. Reportedly 90 per cent of applicants don't make the cut, with one former Kiwi sniper saying that inaccurately assessing distance or range is the downfall for most.
It's the same for the STG - a tactical unit set-up 40 years ago as the police anti-terrorist squad. Its members shot dead David Gray at Aramoana in 1990, after he killed 12 people.
Since 1991, its 36 full-time members across three units throughout the country have been tasked with jobs that are beyond the capabilities of the Armed Offenders Squad (AOS) or traditional policing: terrorism, highly dangerous gunmen, State visits, and spying on organised crime.
Carter says each "operator" is an assault team member but is also trained across a number of disciplines. They then diversify into specialist roles, including snipers, medics, tactical ropers or climbers, and breachers or explosive experts.
Many of the snipers - army and police - grew up hunting pig and deer in New Zealand's mountainous bush:keen shots and masters of stealth, camouflage and reconnaissance.
2/1 sniper team leader Corporal Paul Gernhoefer says real hunters "don't mind getting wet and cold and doing whatever they need to do to get the animal. And that's what we do."
But more than that, it's the character of the person they're looking for. Sound judgment and decision-making. Calm under intense pressure, courage under fire.
"They need to be pretty unruffled individuals who are able to operate to a very high level under extreme stress and when fatigued," Carter says.
Fatigue and the ability to stay focused are also critical. They are the same challenges faced by Anzac "counter-snipers" who operated at Gallipoli, including the legendary Australian, Billy Sing, who picked off Ottoman sharpshooters terrorising the Allied trenches.
The sniper teams are self-sustainable in the field. With packs weighing upwards of 40kg, plus a 7kg rifle and webbing, radio batteries, water, and food, it's not unusual for them to carry 50kg on operations, often trekking in more than 20km before reaching their target destination.
Gernhoefer, a 26-year-old originally from Te Kuiti and Army veteran of eight-and-a-half years, says snipers, a specialist group within the infantry, can carry 72 hours' worth of supplies before needing rest and resupply.
"Water is a killer. The harder the walk in, the hotter it is, the harder it is to maintain yourself," says Gernhoefer. "But fatigue is the biggest challenge for us. You just need that one opportunity ... and it takes a lot of discipline to stay on the target. If you miss your opportunity, you've failed your mission."
They speak vaguely of targets and missions. Not the enemy, or potential fathers and sons.
The mindset appears to focus on saving lives through their actions, more than lives lost.
"Long-range target interdiction is a worse-case scenario which we have to deliver," Carter says, words chosen carefully any time he speaks.
Craig Roberts, in Crosshairs on the Kill Zone: American Combat Snipers, Vietnam through Operation Iraqi Freedom, writes that the sniper "must not be susceptible to emotions such as anxiety and remorse".
They won't talk about specific operations. When I ask Carter if it's true that his lot were scattered through the ragged hills around Queenstown when Prince William and Kate were on their Royal tour here three years ago, he strokes his greying beard and stares back at the range.
This morning, they zero their scopes 100 yards (91m) back from the target zone - a man-made embankment, like a giant grassy door-stop. Or rather a bullet-stop.
The guns are AW and DMW 7.62mm rifles. The DMW stands for Designated Marksman Weapon. They're based on the late-1950s design by Eugene Stoner who came up with the AR-10 battle rifle to equip US troops. Accurate to at least 800m - although the military can push out beyond 1km.
Some are still the old-fashioned bolt-action. That means the sniper must reload the chamber after each press of the trigger.
Some rifles have a small canvas bag attached to catch the expended round or "brass". Others puff on to the ground, to be picked up later, and counted for service records.
They pick up their gear and move back to the 200-yard marker. Four pairs line up at a time. When not shooting, they chat and laugh quietly, standing in circle groups of fours and fives. Quiet encouragement.
It's slick. They run through various scenarios. Co-ordinated shots, solo rounds, aiming at four "sentries" walking on patrol in the distance.
In reality, it's four military personnel who must have lost a bet, tasked with holding up head-sized targets on long poles behind the grass embankment while they are blasted with incredible precision.
They aim for the head. "The medulla oblongata shot is the most coveted shot, the epic shot. Entry through the mouth or the eyeball is also acceptable," Anthony Swofford writes in Jarhead.
But before they pull the trigger - between heartbeats - the amount of variables the two-man teams must take into account is astonishing.
Wind, temperature, altitude, calibre of projectile, target movement, angles ... fair enough. But from around 800m-1000m, things start to get truly scientific. They start talking about light source, barometric pressure, the curvature of the Earth and "spin drift" otherwise known as the Coriolis effect.
"Sorry lads, you'll need to explain that one," I say, pen poised on fresh notepad page.
Gernhoefer, who Carter calls "the guru", explains that, since the Earth is spinning over a long distance, it will have an effect on the bullet. It will drift with the planet's rotation - to the left in the southern hemisphere, to the right in the north.
"The closer to the Equator, the more effect it'll have," Gernhoefer says.
The spotter, the senior partner who looks like a bush in his ghillie suit, squats behind the prone sniper and does the calculations. He refers to charts, sometimes uses a calculator, often it's done mentally, within seconds. Time can be precious.
"This allows the shooter to focus fully on his or her marksmanship," Gernhoefer says.
The spotter uses a powerful scope, or optic, a Leupold Mk4 with MIL Dot reticle or crosshairs, similar to the one mounted on the sniper's rifle. They are wired to each for other sound.
When the high-velocity shot is fired, from about 300m and beyond, the spotter can track the flight of the bullet as it leaves a vapour trail in the air.
"In the right light, you can actually see the back of the bullet and see its arc as it disrupts the air. A good spotter can then use that to call any adjustments that may be needed," Gernhoefer explains.
As the training goes on, they keep moving back up the range - 400 yards, 600 yards. A round cracks and echoes. The mechanical crunch of the bolt action puts another round in the chamber.
The spotter assesses the damage. "Perfect bro, right in the nose."
• Finnish Army sniper Simo Hayha, nicknamed 'White Death', was credited with 505 confirmed kills in 100 days fighting the Red Army during the 1939-40 Winter War between Finland and the Soviet Union.
• Roza Shanina was a Soviet sniper credited with 59 confirmed kills during World War II. She died in January 1945, aged just 20.
• US Marine Corps Gunnery Seargent Carlos Hathcock was a legendary sniper of the Vietnam War with 93 confirmed kills. The Viet Cong gave him the name Long Tr'ang, meaning white feather, because Hathcock always wore a white feather in his hat while on patrol.
• A sniper from Canada's elite special forces reportedly shot and killed an Islamic State target from a "record-breaking distance" of 3540m in June. The shot was believed to be more than 1000m further than the previous longest distance for a confirmed kill shot.
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