Just measured 12 cylinders. Length varied from a low (1) 1.607" to a high (1) of 1.615". 3 were 1.610". 3 were 1.608" and 3 were 1.609" and 1 was 1.612"
These cylinders were from low backs, high backs, .38 spl, .357 mag, and 9mm. Average is 1.609"
But remember, the fit in the frame (barrel/cylinder gap and rear headspace) comes from the crane barrel and the ratchet, barrel set back and the cylinder length. But since the cylinder length has been a pretty good constant through the years, I would concentrate on the crane barrel and the ratchet as possible suspects, although probably not causing the OPs problem, I would be concerned about the very small B/C gap and want to open that up just a tiny bit.