Re .Long range as in greater than 200-300yds.
Granted that the wind deflection at the ( slower than) transonic velocities will be less, but 
OTOH, the Elevation variation will be greater per velocity extreme spread at the lower velocities than at the starting out velocities of 1300-1400fps.
Trade off time. I think I rather work with my 40 cal 373 gr elliptical at 1375fps than a slower bullet with its paper less wind deflection. 
also, a pointed ( read spritzer) bullet will be MORE affected by head /tail winds- they will "sail like a kite" Even at only 4-500yds.. been there , done that. 
Elliptical nose for me for "all around work".
PM me for a drg of my 40 cal Elliptical minigroove bullet I had Steve Brooks cut for me. It works in 16 twist out to 1K.   
beltfed/arnie

beltfed wrote on Jan 23^rd, 2016 at 10:04pm:

Arnie - how long is your bullet and what does it weigh? A few of us shoot the BACo 400gr Kidwell Money bullet out to 1000yd with good effect.

to add to what dave said, s.g should be 1.4 min at the target for black powder bullets.
given that 308 match bullets lose about 25% of spin at 1000 yds, things get interesting.
given also that bpcr bullets are transonic, and hence subject to all sorts of instability problems out to about 500 yards, do not be scared to look for an s.g. of 1.8 to 2.0 at the muzzle for long range bullets.
faster spinning bullets have a slightly greater yaw of repose than slower spinning ones, thus a slightly reduced b.c.
however a bullet that wobbles due to any momentary instability has an even lower b.c, and this being variable will induce vert into a group.
the faster spinning bullet at say s.g 2.0 at the muzzle will still be accurate if it is a quality bullet.
it can then get through the transonic zone, and lose some spin, still being stable at the long range.
faster spinning bullets also cope better with wind shear.
for close range shooting like scheutzen, 1.4 to 1.5 s.g at the muzzle might well be better for the extreme accuracy required, as precession and nutation happens quicker than with faster spin.
keep safe,
bruce.