Cheers Goldie.
I’ve just ordered a mould from CBE (and a set of Simplex Master dies as my Super Simplex dies are no good without a press.....not sure where that went) which
goes .321 I reckon(?). Also have a couple of hundred of the HRBC 128gr RN’s you’re using. We shoot a scaled back silhouette match at my local pistol club and this info will be of great assistance in getting my Cadet knocking those pesky little turkeys over!!
Just on the .303 situation.....I reckon you’re on the right track. The best shooting cast proje I have for .303 is the old Lyman 314299 casts at 192gr with range trash. .314 (seen worn examples using .316.....really nice stuff using .312).
Cheers again and good luck with the .303!!