Re: Ranging reticle with BDC for .223?
The downside to the BDC reticle is that it is designed for a specific load, rifle, and condition. More often than not, you will find the BDC wont match your rifle/loads trajectory.
Your best bet is to purchase a scope with a reticle you can range with, you can use the reticle for holdovers or dial from your turrets. Many ballistic programs will give you all the required info once you can determine velocity.
If you are set on a BDC scope, I have used the ACOGs as well as the IOR Valdada 4x24 M2, both work well assuming you can handload to match the specific velocity that matches the BDC.
Kirk R