And John Burns used a BDC turret that he personally designed and has used extensively. The average hunter could not realistically expect to execute a 2 for 2 on an 1100 yd shot with near the understanding, speed, accuracy, efficiency, and success of John Burns with the same scope, unless Mr. Burns himself dialed the turrets for the shot. My opinion is that BDCs are best suited to the elevation and bullet/load they were designed for out to approximately 650 yds, without the use of field-ready ballistic software. The more knowledgeable and proficient a person becomes with the BDC turret equipped scope and rifle combination, the more he might be able to stretch this range. If one practiced from a stand location over the 1100 yds to the hillside/opening and developed proven drops & turret adjustments for the shot before the killing shot on an animal later standing on the hillside/opening, then any scope can perform at longer distance well under those known environmental/atmospheric conditions and pre-proven turret adjustments. Move to another elevation, temperature condition, or angled shot and you'll be much less proficient using solely the BDC turret and a rangefinder.
The videos showing the range, dial to the yardage number, and shoot can be misleading until a person gains a thorough understanding of external ballistics and the affects of differing environmental/atmospheric conditions and differing inclination or declination angles of shot.
Of course, add a PDA or PPC with field ballistics program capability (as Shawn Carlock presents in his long range hunting video) to a BDC turreted scope and it could be as effective as any other moa or mil turreted scope at very long range, for an informed individual.
Point is, a field ballistics program is a more accurate method of determining predicted drops at any extended range than simply using a custom BDC turret and range finder. The longer the distance, the greater the advantage to the PDA/PPC system compared to the BDC turrets only method. The only advantage to the BDC turrets is that for shorter to mid-range shots, the method can allow one to get off an effective shot more quickly. And there's no denying that advantage. It does no good to exactly determine the necessary turret adjustment if the animal has split by the time you're dial in. So there are pros and cons.
If you're dedicated to preparing for, and taking truely long range shots at variable elevations and under variable atmospheric conditions and shooting angles, the PDA/PPC is really the only way to go about it. And at very long range, time is not usually of the essence. If you don't plan to specialize and prepare for the 700 plus yd shots, and are content taking game out to ~650 yds, the BDC turreted scopes could be a good match for your use.
