Thanks for the response, it is really helpful. I believe the 1:11 twist would be a safe option, especially with the restrictive option of powders here in South Africa. My preferred hunting rifle is a 308Win with a 1:12 twist barrel. This rifle definitely prefers 150gr bullets to 168gr and heavier. That was the reason for the initial request for information.
Using this calibre for sport shooting over distances up to 800 yards is however unfamiliar territory for me.
Thanks again for the help and also for this great web site.
Kobus Visser
South Africa