Off target : It has been claimed the G36 ( pictured ) does not shoot straight when it overheats at 30C . The G36 was created for the requirements of the German armed forces but it is also used as an infantry weapon in around 50 countries . It is used in Britain by counterterrorism police . First made : 1995 . Calibre : 5.56 mm x 45 . Magazine capacity : 30 rounds . Weight : 3.63kg . Length : 755-1,002mm . Use in the UK : Between 2,000 and 3,000 G36 rifles belong to police forces across the country . An assault rifle used by counter-terror police does not shoot straight when it gets hot , tests claim . The Heckler & Koch G36 is inaccurate by up to 20 feet at long range when temperatures top 30C , it was found . The weapon also becomes unreliable when it is left in direct sunlight , exposed to humidity or fired repeatedly , according to a confidential report . The findings have prompted an urgent inquiry into the German-made firearm , which is used by law enforcement officers across the UK . Britain 's police forces use a short-barrelled version of the weapon known as the G36C – and have a total arsenal of up to 3,000 . Counter-terror and armed response unit officers use them when they need more firepower than the 9mm pistols or carbines they usually carry . Now experts at the Home Office 's Centre for Applied Science and Technology ( CAST ) will lead the inquiry after Germany said the rifle had 'no future ' with its military . A leaked report commissioned by Berlin 's defence ministry said the precision and accuracy of the G36 deteriorated when it overheated , either because of the temperature or rapid fire . It concluded that when the atmospheric temperature reached 30C ( 86F ) , bullets missed their mark by about 50cm ( 20 inches ) at a range of 200m ( 220 yards ) and by up to six metres – about 20ft – over 500m ( 546 yards ) . Reports in the German media claimed it also started to become seriously inaccurate after it fired just two magazines – about 60 rounds . Heckler & Koch denies the weapon is inaccurate . But Britain 's National Police Chiefs ' Council has asked CAST to consider the findings . Simon Chesterman , spokesman on armed policing , said : 'The reliability of any weaponry that the police service uses is of paramount importance . ' Superintendent Kevin Carter , of the Civil Nuclear Constabulary , which guards Britain 's atomic plants , said it had not experienced problems but added : 'We will monitor the situation and await advice from CAST . ' UK police are said to be desperate for a new firearm to help curb the threat of terrorists carrying high-velocity automatic weapons and using body armour . Officers are finding it increasingly difficult to maintain their ageing armoury and are concerned by the discovery of heavy weapons among criminal gangs . Under review : Deputy Chief Constable Simon Chesterman ( pictured ) , the spokesman on armed policing at the National Police Chiefs ' Council , has said the findings will be referred to the Home Office for urgent review . In service : The weapon is used by police forces across the UK . They have a total arsenal of between 2,000 and 3,000 G36C rifles , a version that has a shorter barrel than Heckler & Koch 's standard-issue rifle . The G36 , created in the early 1990s for German troops , is also used in around 50 other countries . British Special Forces used it in Iraq but reports surfaced in 2012 that G36s used by German soldiers in Afghanistan would overheat during prolonged firefights . In the German report , experts tested 304 rifles – including the short-barrelled version – and found none passed precision tests . They concluded : 'The causes for the reduced accuracy do not lie in one of the components ... but rather in the whole system . ' Lieutenant-Colonel Markus Thull , of the German defence ministry , said the G36 was now 'not fit for purpose ' . Andreas Heeschen , of Heckler & Koch , said the rifle complied with its original specifications , but a gun 'designed for the Cold War ' did not meet current requirements . He added that the company had received no complaints from the 50 countries where the weapon is used but vowed to assist with the UK review .
Leaked report suggests G36 rifle did not shoot straight when it overheated . Score: 6