A public inquiry into the non-combat deaths of hundreds of British soldiers is being urged by the family of a teenager who died at Deepcut army barracks.
Geoff Gray died in 2001 and James Collinson died the following year
Geoff Gray's 17-year-old son, also Geoff, was found shot dead at the barracks in Surrey in 2001.
On Wednesday, Mr Gray is set to renew calls for the 1,700 non-combat deaths of soldiers since 1990 to be investigated.
He will be backed at a House of Commons press conference by Amnesty International and the Labour MP for Hull North, Kevin McNamara.
In the Army, you're nothing but a number, but as soon as you're dead that number is scratched out straightaway
They say a wider public inquiry is needed because of growing concern at the way the deaths are investigated, amid reports of bullying of young recruits.
Mr Gray, now living in Hackney, east London, told BBC News: "What we need is a full public inquiry into non-combat deaths within the UK.
"There's an awful lot of young soldiers being killed in various circumstances and I believe that an awful lot of those soldiers' deaths have not been investigated correctly.
"I think the Army has had a blase attitude towards young soldiers - you're in the Army, you're nothing but a number, but as soon as you're dead that number is scratched out straightaway."
Mr Gray said Surrey Police assumed his son had committed suicide, within hours of his death, without properly investigating.
He said: "Those young soldiers signed up to serve their country. I think it's about time their country served them by giving them a decent inquiry into how they died."
He added: "The British army has time and time again closed ranks and not investigated deaths as closely as they should have."
Cheryl James and Sean Benton both died at Deepcut in 1995
The four privates who died at Deepcut are Cheryl James, 18, from Llangollen in north Wales; Sean Benton, from Hastings in East Sussex; Geoff Gray, from Seaham in County Durham; and James Collinson, from Perth, Scotland.
Surrey Police have said there is so far no evidence of any third-party involvement in the deaths, but the investigation continues.
The Army maintains the soldiers took their own life.
An independent forensic expert Frank Swann was hired by the families to investigate the deaths and has yet to report his findings.