Paul,
the 139gn Scenar is a relatively low-BC bullet compared to some other 140s in the calibre. It has a very large meplat (but that can be overcome with a Whidden or other make of bullet pointing die), but also a rather blunt front-end of 9.7 cal radius tangent ogive compared to 18.32 cal R for the 130gn Berger VLD, 18.27 cal R for the 140 VLD and 15 cals R for the relatively new 140gn Berger Long-Range BT. The VLDs are of course secant-nose form bullets and that can impose limitations on their use in F-Class as they made need to be seated hard into the lands to shoot well. The Scenar and Berger L-R model are tangent ogive and therefore much more jump-tolerant, usually easy to get to shoot well and you can seat them a bit off the rifling, so there is no question of pulling the bullet with all that entails if you get the command to stop shooting and unload for any reason.
Taking these four bullets, and using Bryan Litz's actual shooting derived data over long ranges ("Applied Ballistics for Long-Range Shooting", a book that is a must-have for the long range BR and F-Class shooter who handloads and has a choice of cartridge / bullets) and Berger Bullets' G7 reference standard PC ballistics program, the four come out as follows for retained 1,000yd velocity and wind drift in inches in a 10mph 90-degree crosswind:
130gn Berger VLD at 2,850 fps MV - 1,423 fps / 77"
140gn Berger VLD at 2,750 fps MV - 1,470 fps / 71"
140gn Berger BT L-R at 2,750 fps MV - 1,435 fps / 74"
139gn Scenar at 2,750 fps MV - 1,365 fps / 81"
Remember other factors. External ballistics (MV + BC) isn't everything. Accuracy + small MV ES spreads are mighty important especially in long-range F-Class, and the 139gn Scenar has a very good long-range track record in the UK in both BR and F in various cartridges. Secondly, the MV you can obtain allied to accuracy etc will likely vary according to bullet make, and a slightly lower BC bullet may perform better than a 'superior' example if it can be driven 100fps faster from your barrel.
Then don't get massively hung up on comparing 10 mph crosswind drift figures unless you shoot on ranges with really wild weather. It's the wind strength / direction changes that matter, so an extra 4" 10mph drift figure will likely be reduced to a half or quarter that in a real range situation, and you need to decide how important that is. Remember, that learning to read the wind and adjusting your aim accurately will see much greater score improvements than using bullet A compared to Bullet B in any given cartridge. When you get to 10" (in the 10mph crosswind) as between the best and worst above, that does start to have an effect.
You don't say though at what ranges you intend to compete. At up to 600yd, the ballistic performance differences between the bullets is much reduced and the 6.5X47L with an optimised load and hence good grouping ability is a very good choice at up to 600yd. At longer ranges, you can have a great deal of fun and will hit the black consistently, but will unfortunately be at a competitive disdavanatage to the 'big boys'. The pace in UK F-Class Open at long ranges is set by 7mmWSMs at 3,000 fps +. A 0.284" 180gn Berger VLD at 3,000 fps (and many competitors run at still higher MVs) travels at 1,736 fps and drifts 56" in a 10mph crosswind at 1,000yd, so any 6.5X47L combination is at a disadvantage.
I hope these thoughts help, and good shooting. The AI in 6.5X47L is great choice for a multi-purpose competition rifle.
Laurie,
York, England