Hardin,
I am not an expert re the 9.3-62 but I believe the European standard is close to 1-14. I would pick the 1-12 but a 1-10 is a little too much.
Mines a 1-10 and no issues with 250 ABs, TTSX and Swifts with Accuracy.
I don't know barrel twist science but my factory rifle came with a 10 twist barrel which surprised me. I called to confirm and yup, that's what they spec'd. What they couldn't recall is why they spec'd that twist.
In any case, I have loads from 185 grain Lapua to 300 grain A-Frame and they (as most 9.3 owners already know) all group well. In fact, the 300 grain A-Frame load shoots so well (thanks MD) it's now my standard 9.3 load. I am however, tweaking the 250 grain load for an upcoming Sable hunt...