Firing Range for Essex

Essex Police currently own a small 25m firing range which we can use for practice and training. However, a significant amount of training and qualification shooting must take place on a 50m firing range. As Essex do not own a facility of this size, we currently have to utilise ranges owned by other Police Forces and the Military in order to ensure our firearms officers are adequately trained and qualified.
Essex Police would like to understand what facilities exist in the county that could be made available.