The VihtaVuori pistol powders are single base, porous powders that also meter well through most powder measures. Slowest of the N300 Series, this powder has a burn rate like Blue Dot, "Hi-Skor" 800-X or No. 7. A good powder for 9mm Luger, .38 Super, .38 Special, .357 Magnum, 44 Magnum and .45 ACP.
Big Book Catalog, Issue:67, Page:527
Sinclair, Issue:4B, Page:094