Fifty years ago, Jeff Dalley was a 21-year-old soldier digging in for the fight of his life.



When the dust had settled, he had survived the bloodiest and most protracted engagement of Australia's decade-long involvement in the Vietnam War, an engagement in which 26 Australians were killed in action and 100 were wounded.



Jeff Dalley at Nui Dat in Vietnam in 1968. ( Supplied: Paul Braybrooke )

The battle over two small patches of ground known as Coral and Balmoral would rage for 25 days, during which the young lance corporal would help repel mass charges by the enemy and see one of his best mates killed in a rocket attack.



Nearing his 72nd birthday, Mr Dalley has recalled what it was like serving as an infantry rifleman with 3rd Battalion, The Royal Australian Regiment, better known as 3RAR by those who wore the army uniform.



Mr Dalley described the assaults by North Vietnamese and Viet Cong forces at the Battle of Fire Support Bases Coral and Balmoral as "human wave attacks".



"They just never stopped coming. They would use their fallen as cover," he said.



"They would pretend that they were dead and just lay there, but at the same time when darkness came they would crawl closer to you and they would blow the wire."



Battles lasted more than three weeks

The battles in May and June 1968 involved almost 3,000 men — Australia's first brigade-sized operation since World War II.



Coral and Balmoral were fixed next to a route used by enemy forces approaching or departing Saigon and nearby Bien Hoa.



Mr Dalley's battalion was sent to establish Coral on May 12 as part of Operation Toan Thang, the US-led response to the communist Second General Offensive, or "Mini Tet".

Jeff Dalley after completing his army recruit training. ( Supplied: Paul Braybrooke )

The men immediately began work on the defensive positions, and Mr Dalley remembers digging in under fire.



"It was just like a gigantic football field. There was a few little shrubs and the jungle further out," he said.



"The only cover we had was when we dug our own holes."



Tanks and artillery fired at point-blank range

The bases were filled with artillery, mortars and armoured vehicles supporting the infantry.



Mr Dalley still applauds the actions of an artillery sergeant at Coral when the enemy threatened to overrun the Australians.



"They had broken through and got to one piece of artillery and they were trying to turn that around to fire on the Australians, but the sergeant had the foresight to remove the firing pin, otherwise who knows what would have happened," he said.



Exhausted and at the end of one of the longest weeks of his life, Mr Dalley's unit was sent to establish the Balmoral base on May 24.



Four Centurion tanks arrived to provide fire support.

3RAR conducting a routine perimeter sweep of fire support base Balmoral during the Vietnam War. ( Supplied: National Vietnam Veterans Museum )

Diggers almost overrun but 'we'd hold em'

At 3.45am on May 26, Balmoral came under a barrage of mortar, rocket, machine gun and small arms fire.



But with the support of tanks and armoured personnel carriers, and artillery fire from nearby Coral, the Diggers were able to push back the North Vietnamese attack.



"Thankfully, for the tanks and APCs, that stopped them," Mr Dalley said.



"The tanks were using splintex [anti-personnel rounds] and the armoured personnel carriers had .50 calibre and .30 calibre machine guns, and they just raked the place.



"A lot of people say if it hadn't of been for the armoured, we would have been run over by the enemy.



"But you ask the infantry and we say 'No, we'd hold em'.



"We didn't want the tankies to get the glory and the tankies didn't want us to get the glory, so we'll call it a 50-50 split."



Close friend killed in rocket attack

The known North Vietnamese and Viet Cong losses around Coral and Balmoral were 276 killed, nine wounded and 11 captured.



But the fatalities were estimated to be much higher, as the enemy was known to carry their dead off the battlefield.



Among the Australian fallen was 20-year-old Alan John Cooper, a talented Australian Rules player from Adelaide, who was killed by a direct hit from a rocket on May 26.

Jeff Dalley (far left) with his infantry section, including Alan Cooper (third from left) who was killed at Balmoral. ( Supplied: Paul Braybrooke )

Cooper, or "Coop" to his mates, was Mr Dalley's second-in-command in their nine-man rifle section.



"That was a pretty bad day [May 26, 1968], but we all knew the consequences," Mr Dalley said.



"AJ Cooper was a really top bloke, everybody liked him, and it was just a shame that it went straight down his hole.



"The rocket went into his hole and it destroyed him."



Anniversary brings back raw emotions

Mr Cooper was laid to rest with full military honours in Adelaide, one of more than 500 Australians killed in Vietnam.



Mr Dalley expects the 50th anniversary of his friend's death to hit him hard.



"I always remember Coop on the 26th of May, because my birthday is the 27th," he said.



"I like to have a quiet time with my memories there and usually have a few beers and just think of Coop. He was a good mate."

Gary Cooper, next of kin to fallen soldier Alan Cooper, gives a reading at the Australian Vietnam Forces National Memorial in Canberra. ( Supplied: Department of Defence )

Mr Dalley met Mr Cooper's two brothers at a reunion in Canberra a few years ago and wrote an emotional letter to his parents, telling them how respected Coop was among the men.



"I never got a reply back which I'm grateful for in one way, because you talk about it and talk about it and it becomes embedded," he said.



"But I always remember Coop."

Many close shaves in year-long tour of duty



After Balmoral was closed, 3RAR returned to the Australian taskforce base at Nui Dat, but Mr Dalley's tour of duty in Vietnam was not over for several months.



Wounded once in action, Mr Dalley had other shrapnel injuries, but the reality of the war only hit home after a near miss on a later patrol when his unit was ambushed by a machine gun team.



Jeff Dalley heading out on patrol in Vietnam and sending a message home to his parents. ( Supplied: Paul Braybrooke )

"I had shrapnel and bullet holes through my shirt," he said.



"Some of my [rifle] webbing had holes through it and there was a bullet hole through the middle of my hat.



"I've got to admit when that happened I had a breakdown.



"I don't know why but I never had a drop of blood on me, but my clothes were just ripped to pieces from the shrapnel and the bullets, but I didn't have any holes in me."

Veterans abused on return from war



Mr Dalley, originally from Benalla in Victoria, moved to the gold-mining hub of Kalgoorlie-Boulder in Western Australia in 1974.



He said settling back into civilian life was something he struggled with for decades, admitting he never talked about the war.



Jeff Dalley at home in Kalgoorlie with his partner Rita Crist and dog Merf. ( ABC Goldfields-Esperance: Jarrod Lucas )

"I had a lot of problems. I had a lot of mood swings and changes, jobs here, there and everywhere. I wanted to be alone," he said.



"I never advertised the fact that I was a Vietnam veteran because when we marched through Adelaide we had eggs, tomato, paint, everything thrown at us.



"It was better to shut up and try and get on with your life, but that was hard because it's a different life altogether from the life you experience when you're in the army."



Battle honours for Vietnam veterans 50 years on



At a national memorial in Canberra on Sunday, the Chief of Army Lieutenant General Angus Campbell awarded the Unit Citation for Gallantry to 3RAR for its actions at Coral and Balmoral.



Mr Dalley said it meant a lot to him and his mates.

Chief of Army Lieutenant General Angus Campbell attaches Coral and Balmoral sashes to the Colours during the national commemorative service in Canberra for the 50th anniversary of the battles. ( Supplied: Department of Defence )

"The whole time you were there you were walking on eggshells," he said.



"The slightest little noise you would hit the ground, take cover or you just got used to what was being fired in or out of the base.



"The whole time from the day we got there to the time we left you were on edge. You didn't trust anybody other than your mates."