Thanks for adding the ED value. I take it that's with the 100 gr head?arrowhead said:They will be about 345 f.p.s. with the 100 grains and 338 with the 125 grain heads.
Scope height is measured from center of arrow to center of scope. (I use 2.15)
I like to calculate the ED from POI. (point of impact) when I don't have a chronograph available.
ED Calculation from POI
Calculating the ED Value from the position of the Point of Impact can give accurate results if the various measurements are done with precision. This particular method of estimating the ED Value value is especially useful if used in conjunction with published manufacturer's ballistic data.
When the applet opens, the various textboxes are filled with data from the main BRC application (Muzzle Velocity, Scope Height and Zero Range) and the POI is calculated (based on a target range of 2 x Zero Range). Any or all of these textboxes can be altered to suit your particular circumstances without altering the Data Input Panel of the main BRC application. For example, if the maximum range that you have available is just 40 Yards then change the @ Range value to 40 and, after carefully measuring the vertical distance between the aim-point and point of impact, enter the measured POI distance in the Point of Impact textbox. Click on the Calculate button to calculate the ED Value value. Click accept and it will save the ED value.
Sounds very confusing at first, but once you get the hang of it...it really isn't.
I found a chart we used for a Terminator. The ED value was .0351 with that particular bow/arrow combination.