No. The two cartridges, the old 6.5x70R and the “new” 6x70R have quite unique dimensions. While the 9.3x72R and many other cases based on the old British .360 have a base of 10.91 mm = .430” and a rim of 12.35 mm = .486”, the two “pencil cartridges” 6 and 6.5x70R are both base 9.0 mm = .354” and rim 10.7 mm = .421”. That’s about the base dimensions of a .32-20 case, while the 9.3x72R has base dimensions similar to the .30-30.