I've not seen or heard of one used in silhouette and I think your bullet question pinpoints the reason: this small case probably wouldn't throw the heavy bullets fast enough. Stress on the "probably" because I don't really know, but if you're going to shoot a .30 you might as well smack the ram with at least a 180 and that's going to be tough with 30 grains of powder. I understand that the benchresters get 8000 rounds of great accuracy but they're using 118-125 gr bullets and 17 twist.