Idaho, thanks for an insight, only need a small increase in velocity so i might drop approx 5-10gns in volume & see how that goes. We do have to produce two loads for testing if required, otherwise we're disqualified for that BGR event.
Have to say the BGR guys are a helpful bunch here in Oz & its nothing for them to lend a rifle & loads for an event or two. These aren't your average guns or loads, mostly "heavies" to get the juniors hooked........A terrible bug is the big bore bug when she bites!
Makes very interesting reloading & testing all that more fun.
Cheers mate
93x64mm