Well, yes and no - I said they were about the same length. I just pulled out my Bach Strad 239 C trumpet and compared it to my Bach Strad 43 Bb trumpet. The bell tail on the 239 is 1/4" shorter than the 43 bell. The main reason the C trumpet valves are so much closer to the player is the shorter mouthpipe on the C (mine has the standard 25C mouthpipe), which locates the mouthpiece receiver closer to the valves. Using length alone as a criteria, putting a 239 bell on a Bach Bb trumpet would require only an additional 1/8" pull on the tuning slide to be in tune.