Vihtavuoris N550 rifle powder was originally developed for .30-06 Springfield and .308 Win. calibers in the late 90s. The N550 is an ideal fit for many of the 30 caliber magnums with lighter bullets, but also useful across a wide range of bore sizes in various shooting disciplines. It is an excellent powder for .30-06 Springfield hunting rounds with heavier bullets, and also for other more powerful loads of 6,555 SE, .308 Winchester plus many others.