The police force looking into the deaths of four recruits at Deepcut Barracks has said it is "deeply unhappy" with the independent investigator hired by their families.
Relatives of the dead refused to believe it was suicide
Surrey Police accused Frank Swann of discussing his findings with the media rather than the official inquiry team.
Officers said Mr Swann had sent them only a brief outline of the conclusions of his six-month investigation, with no details of the evidence he had to support them.
Surrey Police said they had received the single page on Friday, only days before the force was due to announce the findings of its own year-long inquiry into the soldiers' deaths.
All four died of gunshot wounds at the barracks between 1995 and 2002 - and their families have refused to accept the theory that they committed suicide using their own rifles.
A Surrey Police spokesman said: "We are deeply unhappy that he (Frank Swann) has given so little detail to the official investigation, but has given more to the media.
"We are not trying to rubbish Frank Swann, we are trying to express our frustration at the lack of information that we have got from him even at this late stage."
The spokesman said the force was also "extremely concerned" that Mr Swann might prejudice any future court proceedings by discussing his findings in the press.
Surrey Police were forced to postpone their planned briefing indefinitely after receiving Mr Swann's report, saying only that there were "differences" between his conclusions and those of the other forensic experts they had consulted.
Frank Swann it was "highly unlikely" the recruits shot themselves
But Mr Swann told the media that he thought it was "highly unlikely" many of the fatal bullets were fired by the recruits themselves.
Surrey Police had earlier said it had yet to find any evidence of third party involvement in any of the deaths.
The force has now arranged a meeting with the Forensic Science Service and the German Bundeskriminalamt (BKA) to discuss their findings.
A Surrey Police spokesman said officers from the official inquiry team were "very anxious" to read Mr Swann's full report so they could examine his evidence.
A team of 30 detectives from Surrey Police spent a year examining the deaths of the four soldiers at the Surrey barracks.
They were Private Geoff Gray, 17, from Hackney, east London; Private Sean Benton, 20, from Hastings, East Sussex; Private James Collinson, 17, from Perth, Scotland and Private Cheryl James, 18, from Llangollen, north Wales.