Originally Posted by Garandimal
Originally Posted by beretzs
Originally Posted by Garandimal
Is this a difficult question to answer?

What is the wind difference, of known BC, at 400 yds.?

Or drop, for that matter?


BC's only real value is Energy down range.

... and the .270 Win., even w/ flat based PSP bullets like the 150 gr. NP, has plenty for most game, even at 400 yards.


BC - is a placebo for marksmanship.




GR


His chart shows it pretty well

250’s started at the same speed.

.247 BC drifts 31” and has 1050 FTLB at the 400 yard line.

.648 BC drifts 9.7” and has over 2300 FTLBs at the 400 yard mark.

But that doesn't answer the question.

Now, given, say, a flat-based .270 Win/150 gr. NP (BC= 0.465) at 2900 fps at the muzzle and a 200 yd. zero.

At 400 yards, w/ a full deflection 10-knot wind, it's:
- doin' 2150 fps.
- carryin' 1540 ft-lbs.
- droppin' 21 in.
- blowin' 12 in.

As both the velocity and energy are adequate for that bullet?

... I'm only correcting for the drop and wind.

How does a little extra BC change that?


Correcting less - doesn't replace correcting correctly.

BC - is a placebo for marksmanship.




GR

If you can judge a 7MPH wind or a 14MPH wind every time, right on the money, you’re right, adding BC makes no difference cause you’ve got it licked.

Semper Fi