I've been using the .312 Lee 185gn mould, beagled out to .314 and then powder coated on top for lubrication and a diameter at the widest point of .316 and then at 90deg they measure .314. I've modified a Lee push through sizer to .316 and the PC'd bullets only make contact at the 'wide' points of the bullet as they go through. The throat slugs out at .316 with excellent rifling which is copper-free after lots of work.
The current load is 16gn of 2400 with Federal Match primers in neck sized Privi brass and whilst I'm not the greatest shot, accuracy isn't brilliant. I'm guessing the out-of-round bullets aren't obturating due to the light load though they are certainly stabilising. I have no leading after 50 rounds, just powder fouling.
What I would like is a mould that casts a 155-185gn bullet at .316, these seem to be thin on the ground, does anyone have any suggestions for a source before I have a go at lapping out my Lee mould? Shipping to the UK would be a requirement.