I was in same boat. Ended up taking 300 Weatherby brass, running through a friends 7-300 weathered die with expander removed and lately running through 270 Weatherby die with expander removed. From there you can treat as normal !! My neck thickness loaded ran .294-.295 which still was enough clearance without neck turning. Just keep on eye on that.
A little work but at least got barrel broke in and rifle sighted in!!
