1:16 is about limited to a traditional design 45gr. bullet. At the typical cast bullet velo's you cant really get longer, thus heavier, bullets to stabilize by an increase in velo. At least it didnt work for me in 3 Hornets and over 4000 rounds of mostly cast bullets, YMMV. That said, the old 45gr. is really a dandy and has been doing the job for a long, long time. I shot a lot of rounds about as cheap as you can get, mostly at 50yd. target paper going for group size. Funny thing I finally realized is that I had to work at it to get it to shoot as consistently as small groups as a decent shooting .22LR at the same range/paper, side by side, most sessions. Not that it was bad, mind you, 3/10ths " for 5 was a typical good group if I did my part, but I would usually pull one farther out and 'blow the group' (Im my own worst shooting partner).
BTW, I found my best consistent accuracy under 1450fps (chrono'ed), 1350-1450 seemed to be the happy place for my WWt bullets.
