Originally Posted by tbzep

Almost, but not quite. The original Akela-1/Centuri Viking had a different nosecone and the fins had ever so slightly different dimensions, showing that they weren't cut with the same die. It goes without saying that the BT-20 is thinner than the series 7 Centuri tube also. However, the spirit of the design is the same throughout.

The nosecone difference is easy to see. The fin difference isn't quite so easy unless you stack them. I can't seem to find the pic of the fins, but here are the nosecones.