Posted earlier on the NOE Forum. Would function like an adjustable core mould.
Hoping to stir a little interest here, enough to interest Al.
"So, Al... If offered at .451-.452, bored from the base, using the sprue plate to cut a nice flat hunting meplate, in a tall single cavity block, with multiple shallow grooves (to grip paper), and a base plug fitted to a screw bolt going through a threaded plate to adjust length/weight... should be a cake-walk, huh?
Where else can a caster dream away like this?
Heck, a matching base-plug could be offered for shallow cup bases (some BP shooters) while the flat could be adjusted between grooves to produce full diameter or quasi-rebates for different tail-twisting preferences.
1 mould for multiple throats... NOW I'm having fun! "