Kahles, is it a gimmick? : sakomato wrote: sniperafar...

 

It is always best to shoot at the distance when you are setting the marks.  It is easy to do, you can move the marks with any sharp object like a ball point pen.  They will not move on their own cause there is a little tension there and the silver rings where the marks are located are recessed from the black knurled rings of the turret.  The red thingy slips over the silver ring and turns it separately from the turret

 

However, if you are limited by time or availability of longer shooting ranges, then you can take the trajectory from your bullet and set up a target to set the marks at the 100 yard range.  For instance, in the beginning I used a 100 yard zero for the 280AI and calculated the trajectory as follows for a 100 yard target (160 gr Accubond at 3000 fps)

 

100 yards - zero

200 yards - 2.80" / 2 = 1.4"

300 yards - 10.6" / 3 = 3.5"

400 yards - 23.9" / 4 = 6"

500 yards - 43.9" / 5 = 8.8"

 

put some marks on the target and shoot it at 100 yards to set your marks

 

 

it will get you close but you should consider it a preliminary setting of the marks. 

 

Then when you shoot at the longer distances you can tweek the settings a little one way or the other.