This business of BDCs, Ballistics Calculators, Weather meters, etc. are where I have been spending most of my rifle hobby time lately.
Couple of salient points:
1. Hunters (Large Game)
If you shoot/hunt large game only, then by all means take the Weatherby System. Large case, Premium Hunting bullet, High velocity, Flat shooting.
Barrel wear is not an issue, because you don't fire that many rounds in a year. Maybe 1 box at the most?
Hunting scope is fine, because these things are typically point blank or in the kill zone out to over 400 yards for large game. Many hunters have strict ethical rules about maximum range shots, etc.
2. Tactical Shooters
BDCs work well on tactical targets out to just under 1000 yards. Again these targets are fairly large. It appears that most non-military shooters engagement ranges are well under 200 yards, so in many cases only minor elevation and windage adjustments are necessary for this application.
3. Target shooters
Target shooters can win consistently if they can shoot into .5 moa under all conditions. They have sighters, known distances, and other features that simplify the problem for them.
4. The rest of us.
Shooting small targets at short to medium range, and medium targets at extreme range in variable conditions and distances.
Tactical contests and Varmint hunting fall into this category.
Barometric pressure, Ambient temperature, Wind velocity and direction, Barometric Pressure, along with distance to the target all play an important part in this. Knowledge of the firearm's performance under given initial condition are important as well, as every combination of load, barrel length, bullet, etc. have a significant effect on point of impact.
So what do I do.
Equipment as follows:
Horus Ballistics Program/Palm
Leica 1200 RF
Redding Micrometer Sizing and Seating Dies
Berger, Lapua and Sierra Target Bullets
Custom Target Rifle and Scope.
This whole learning process is a lot of fun and while not perfect, answers a lot of questions.
Comments on BDCs
They basically allow the owner to write his come up chart on the knob, for a given set of initial condition. As state in earlier posts, a great solution as long as initial conditions don't change.
A better solution is to take field measurements to adjust initial conditions, and write or print a come up chart for that day. Not perfect, but not bad.
Tons more stuff, but fingers are getting tired. [img]images/icons/smile.gif[/img]