BDC questions

Alderman

Handloader
Apr 5, 2014
1,267
659
I'm not a competitive shooter by any means but post this here because it seems to be the logical place to ask these questions.
I am contemplating purchasing a Burris scope with BDC reticle for use on a 308 hunting rifle. In reality I will accept 1 to 1/2 groups at 100 yards as my hunting shots with this rifle will be within 250 yards.
I haven't done much reading yet but it appears there are charts to show the dead on range for each dot given a certain bullet at a certain speed.

In theory could I site in at 100 yards with each dot thus the center dot would be right on and each dot below would land higher on the target and thus if I have speed and bullet info, make my own chart from the data tables available in the reloading manuals? I'm thinking if the second dot prints say 2 inches high at 100 the dead on range for that dot could be figured and I could use that dot for a shot at that range.

Is this all there is to it or am I missing something here.

Please clue me in as I am likely missing something.
 
I'm not a BDC user but I have watched some videos that explain how they work by different manufactures. Vortex has a very good one that explains how theirs work and would suggest you go to their web page and watch it. They have videos that explains all aspects of their products and are not complicated and easy to understand.
 
yes , you are correct . these lower aiming points will definitely strike the target at a given distance . you can play with a ballistic chart to get an idea where , but you really need to shoot these to prove your correct . the rifles I have the BDC reticles on have a high enough velocity that I use a 200 yard zero . this makes my BDC hash marks match up well to what I want .

I have not looked at many of the different scope makers literature on their BDC reticles . but I did notice that some will tell you to set the magnification to a lower power to get things to match up better . I don't agree with this . if I'm shooting far I want max magnification . I can usually get the scope set up to where I'm an inch high at "X" distance and maybe an inch and a half low at "Y" distance . which is way close enough for a hunting rifle . in the past I have used the Burris BDC . I'm using the Leupold Boone and Crockett now .
 
I created special bdc charts for quick reference for holdover distances and the bullets path from 50 to 300. It seems to be very spot on with the scopes manufacture ballistics program.

An example of one:

ImageUploadedByTapatalk1437367839.080130.jpg

Allows me to either hold over on the tick mark or compensate for the bullets path of within 300 yards.
 
It could help if I actually add my point right?

If you look at the distances next to the tick marks, they vary enough so that I'd be off a little if I trusted them to be 200, 300, 400, 500. The (closest to) hundreds actually land in between the ticks. I'm too lazy to compare the 100 yard impact height to a ballistics chart, but your theory could work. I'd spit out the drop card first and then verify at the ranges if possible- or make a target that has the distances measured and marked above the zero before shooting, so when you are shooting, you'll have instant feedback. Hope that makes sense.
 
If you sight you rifle in for a 200 yard zero, you would be shooting a few inches low at 300 and need no holdover. My hunting rifles are sighted in for a 300 yard zero with an 8 inch drop at 400. Both magnums
 
If you sight the 300yd hash mark dead on at 300yds then you will find the 200yd & 400yd hash marks to be very close when using any reasonable load. At least that has been my experience. Naturally, its always a good idea to confirm just how close by testing at those ranges.
 
Each scope manufacturer has a different BDC ladder design. I have BDC type scopes manufactured by: Kahles, Zeiss, Minox and Leica. I would suggest using the manufacturer's software for that particular scope? Normally the software will offer different trajectories for each bullet manufacturer's loads and bullets.
 
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