I would agree. Even for the 130gr most manufacturers recommend a twist of 1-8.5.
I guess the reason is that a faster twist would compromise velocity with 140gr, particularly for long range.
Your velocities seem a tad low to me. I achieve just a little below QL predictions with RS62 in my 260.
Of course if you really want speed, RS60 is the way to go. Burns hot though.
.223 for me. I would probably prefer 22-250 but i wouldn't be able to use it at Bisley.
.260 Rem or any of the 6.5's would be handy for both fox and deer.