I sure can, but depth of the large grease groove is much more limited than if the mold were cut with a cherry. Which won't make a practical difference in performance.
I have a muzzleloader bullet which hasn't been cataloged for some time, in which I put a small bulge in the forward driving band which fillls the grooves of the rifle to provide a tight grip so it doesn't move off the powder if the gun if jarred, to seal powder gasses upon initial ignition, and provide better centering in the bore than a slip fit bullet.. It drops freely into the barrel up to this band, perfectly centered by the bore diameter band just behind it and at the heel. A bump with a starter engraves the rifling then it is rammed home with the long rod.
But I can make them for the conventional type fit also. It's your choice. In either case, only the back of the bullet bumps up powder pressure, and the degree of upset, or obturation, must be controled by balanceing your powder charge to suit bullet hardness, a standard procedure with black powder loads.