Bell 412 range figures

[thorpey]

Evening everyone, can someone shed some light on the massive difference of the flying range of the Bell 412? I've been googling the information and there are loads of different figures, starting from 310 miles up to and above 610 miles. I know that the figures will depend on equipment carried and there are more efficient engines on later models but that does seem a huge difference.


Thanks in advance for any help.


Regards


Thorpey.