I'm looking to upgrade my scope on my HW 97K .177  Ideally it would be from 4 -16 or so mag and 50mm adj obj  have BDC turrets and mill dot ret of some description. A 30mm tube would be ideal but isnt a must and  i would like the scope to be no more than 13" long  finally as clear a sight picture as you can get for £300 to £400...... 
  
Thanks i look forward to hearing your suggestions.