Hey Doc, I used to shoot a 357 Herrett in a TC for silhouette. The Herrett is shortened about 3/8" going from memory and is blown out a bit with a sharper shoulder. If it's a full length 30-30 case then it is the wildcat 35-30 which had some popularity a few years back, which is why Win came out with the 356 Win, and the 375 Win to replace the old 38-55 which was extremely favored in the eastern hardwoods country and lamented at length when Win ceased making ammo back in the 60s (I think). The good old boys didn't like the new fangled guns that used the 358 Win but wanted bigger bullets than the 30-30 / 32 Spl in the frame of the 94 Win, hence the relative popularity of the 35-30 in 94 carbines. It was a very popular rebore a few decades back for shot out 30-30s and 32 spls.