Not sure about scale as it was a custom design that was made to a size that 'looked about right' the CAD then went to gun smiths who made and proofed it.
Size wise it's very similar to the Kranks ones - it now on sale from the gun smiths direct at http://www.dolphinguncompany.co.uk/i...dolphin-cannon
some videos of mine on my youtube http://www.youtube.com/channel/UCRJPxxth4atmk94oszF3h7g
Thanks
Mark