Originally Posted by Nomercy448

While I'm not usually one to take interest in a 7yr old thread, I'll bite...

I agree with Sheridan, that the large subtension of the circles makes them a rather bad choice, especially at longer ranges where precision POA placement becomes more and more critical.

My major problem with BDC reticles, even with the SpotOn programming, is that they're only valid under one singular set of conditions. Changing ONE variable for environmental conditions will throw the SpotOn estimates for range/circle reference out the window.

For example, WITHIN A MATTER OF WEEKS, I hunted coyotes in these conditions last season:

I did some test shooting to rezero my rifles and test trajectory when I changed conditions. Luckily for me, I was using Varget and didn't get a lot of velocity spread, but my 400yrd drop changed pretty significantly - enough to have caused the difference in a well placed shot and a dead coyote, and a bad shot, or even a miss!!

Central KS 0 degrees, 1200ft 400yrd drop = 36.5" (This is my normal zero)
Eagle colorado, 0deg, 6700 ft 400yrd drop = 30.5"
Maricopa AZ 65degrees, 1200ft 400yrd drop = 32.25" (Same conditions I might hunt in at home during spring/fall, but drier air)

So if I simply relied upon my BDC reticle and SpotOn's estimation for my cold day zero at home, I might have missed by 4-6". Equally, if I zero in the winter then hunt in the spring here at home, I'll see the same type of variability for drop at range.

Now add to that temperature sensitivity for powders. I run IMR 4064 in my .30-06, which has kicked me in the teeth before when we had a heat wave during rifle season, as a -10 degree day runs the same load about 130fps slower than a 65degree day, hitting about 7" higher at 450yrds.

DOPE books and ACCURATE range cards are worth a lot. BDC reticles aren't worth jack.