Re: Leupold + Horus Reticles
"...very precise ballistic reticle" is an oxymoron.
There are no very precise ballistic reticles, because a ballistic reticle, like a BDC (ballistic drop compensation) knob, is calculated accurately only under a single set of atmospheric conditions with a single load.
Change the conditions or the load, and it's not precise any more.
Learn to use the TMR you have, and you'll save money.
For ranges of 600 yards or less, memorize your dope. Beyond 600 yards, you're going to have to compensate for air density - temperature, relative humidity, and atmospheric pressure - as well as muzzle velocity changes with temperature.
If you don't hunt beyond 600 yards, your problem is much simpler. Learn to use the reticle for holdovers and/or holdunders, and you're done. See:
Calculating Holdovers and Holdunders
added: BTW, the Horus is not a ballistic reticle. It's just an extended mil reticle with wind holds.