All photographers were asked to leave the courtroom in Pretoria before Oscar Pestorius' entered.
The magistrate has ruled that the hearing can not be broadcast live, but videos and photographs can be taken during breaks in proceedings.
Pistorius will concentrate on defending himself against allegations that he murdered his model girlfriend on Valentine's morning.
The South African press say the weapon is a key piece of police evidence, but Pistorius' family said the death is a 'tragic accident.'
The family and management of Oscar Pistorius have released a statement disputing the murder charge against him 'in the strongest terms'.