In line with Larry's suggestion... I was having some issues with large groups with heavier charges of Unique in my .303's. Don't recall exact details but I was working up to max. load of Unique under a 314299 (200 gr.) boolit cast from ACWW. As I moved up in powder charge so groups got worse yet I wasn't at max. Recovered boolits showed "skidding" with grooves in boolits wider than lands whereas the barrel rifling is equal width lands and grooves.

I decided to try oven heat treating and that worked for me with both the 314299 with GC and with a 215 gr. PB boolit from a home made mould.

Water dropping from the mould may work and both are easy to try with no other changes. I was using straight COWW oven heat treated. Not going to claim it is the best "alloy" or that I got bench rest groups, just that it stopped the skidding issue and groups tightened up.

YMMV

Longbow