MJC/Skilly
Quite a bit of confusion here, but your figures are probably up to date. Admittedly my information is a bit old, but it came directly from Wulff a couple of years ago. Most of the information is for the older "double" designations. My info from them for the 7/8 is 29.24 grams (450 grains) @ 65'; no info from Wulff on 8/9 or 9/10; 10/11 is 50.9 grams (785 grains) @ 70', 61.2 grams (944 grains) at 80'; no info on 11/12; 12/13 is 60.89 grams (940 grains) at 70', no information at 80'. I also have information from Wulff for the single designated 10 as being 44.5 to 48.5 grams @ 70'. That's halfway between your figures for the 10 and 11 lines.
As I previously posted, I measured my own 8/9 and it measured 37.25 grams (575 grains) @ 70'. It's interesting that those figures would make it a 9 by your figures. What's confusing is that when Wulff changed all their "double" line designations (8/9) to singles, the new number was the LOWER number of the two for the single-handed lines (the old 8/9s are now 8s) and it looks like the new number for the spey lines is the HIGHER of the two (the old 8/9s are now 9s)!
Can I assume you guys got your information directly from Wulff?
Thanks,
Bill