I updated my copy of Oehler's Ballistic Explorer last week and discovered it now includes Lapua custom drag functions, which were developed using Doppler radar. Lapua also publishes a G7 BC of 0.230 for their 0.308 155g Scenar. Another new tool in Ballistic Explorer is the drag analyzer.
The custom drag function is in green with G7 in red. The two plots match up well between 2600 and 1600 fps, but outside that range G7 shows more drag. Still, even with a muzzle velocity of 3200 fps there's only 4 inches difference in drop at 1000 yards.
There's over 50 custom drag functions, and I've only played around a bit, but found that some bullets don't match well with either G1 or G7, at least not at long range.