My 708 had a 1-10 twist and it stabilized up to and including the 168 SMK. Unless you are shooting 175 and 180 SMKs or 168-180 Berger/JLKs, the 10 twist is perfect.
My most accurate load was with 168 Sierras and Varget.
My next best load was with 110 TnTs; that is quite a range.
I guess I am the only one posting on this thread that has actually used a 10 twist and it works great. I see no need for the 9 twist unless he is shooting the VLD heavies.
I like everything about this except the Hart barrel. I have used my last Hart!!!
