I have been atempting to get some info on the basic data that Nikon used when developing the BDC reticle for the Omega scope. I have recieved a response from them but it included a disclaimer about not posting the info to anyone or anywhere else. So, I am not going to give out the specific info they sent me but will give my take on it and the approximate drop data it is based on. Here is what I came up with based on their info and published data.

Bullet 250 grain SST/SW
Velocity 2000 to 2100 fps
Sight In 100 yards for crosshairs
First Circle Down about 3.4"
Second Circle Down about 10.5"
Third Circle Down about 15.5"
Fourth Circle Down about 22"

All drops are averaged (based on sea level and 5000')and based on the scope being set to 9x and using the center ofeach circle for the aim point.

Their published remarks suggest 150 grains of powder and a 250 grain bullet but as we all know, every gun is different and the results are not going to always match their results. i.e. I get similar velocity to theirs using 130 grains of pellets in one of my guns.

With this basic info someone can work up an accurateload with any bullet and run a ballistic table to find the ranges for each circle for that load based on drop. Then test it at the range to verify and fine tune based on actual shooting results.Of course you can do this with any ballistic reticle scope if you know the aim point spacing.

I hope this helps clear some questions up, it did for me.

That's pretty interesting information. I always said, even if you shot something that did not match their drop, if you tested the scope and the levels in it, you could still learn to shoot long distance with it. For instance the drops while they might be different could be learned and the shooter could adjust. After all how many deer walk out at exactly 100, 150, 200, and 250 yards...

Your absolutely correct Dave. All the aiming points do is get you into the vecinity at some yardage. The data they gave me still has 2+inches of varriance at 250 yards when shot at sea level vs 5000 feet so there has to be some fudge factor considered. Actual results WILL vary from advertised spec. That is why I want to know what drops the reticle is designed around vs what load they used in their gun. It only matters what happens in my gun when I'm in the field, not theirs.

Nikon does have directions for "tayloring" the reticle to your load, but to me it makes more sense to give the data on the reticle setup in inches of drop instead of some specific load or work around explaination. Once the drops are known you just have to memorize the yardages that match up to those drops. I think of itkind of like the sight pinsonmy bow, only you can't move the aim points of the reticle so you adjust the yardages to match them.