Vari-Zone scope for an Excalibur Crossbow

[East]

I have recently picked up an excalibur crossbow and it has the "Vari-Zone" scope on it. But i'm not 100% sure what I'm doing with. I was told to sight it in for 20yds then move back to 50yrds and take a shot and adjust the speed dial depending on if its hitting high or low. What i don't understand is...what speed do i set it at? if its shooting high then i know i have to turn it up but how do i know what to turn it up to? kind of confusing to me.

Anyone out there have any experience with this scope/crossbow combo?

 

[cantgetright]

Once its sighted in at 20yds move your target back to 30yds and take a shot using your 20yd crosshair. Then adjust the speed ring until the 30yd pin meets the bolt you just shot. Need a very steady rest for this method as you don't want your aiming point to move while your making your adjustments.

 

[DMS1]

I like to shoot a group at 20 and a group at 50 yards, then mark a line at the center of each group on the target. This is the drop distance at 50 yards. If you back up to 50 yards and hold the crossbow in a rest/vice/sandbags etc, put the 20 yard cross hair on the 20 yard line, then "zoom" the scope until the 50 yard line is the matched to the 50 yard crosshair (while maintaining the 20 yard crosshair on the 20 yard line.

Depending upon your arrow weight, speed and manufacturers' "guess" at ideal drop for each 10 yards, the lines may not be perfect at all ranges. A very heavy arrow drops more from 40-50 than a lighter arrow, you can't change that relationship by zooming. Shoot the bow at each distance to confirm and adjust if necessary