340 Boy,
The Alliant website states 16 is slightly faster than 17. But powders wiith burn-rates close to each other can (and do) switch burn-rates in different applications.
I've used it only in the 6.5 Creedmoor and .260 Remington. It worked well in both, but in the Creedmoor at least one other powder got better accuracy with the same bullet.
