Yes, the 44 Special has the exact same ballistics as the 44 Russian. Though there is a great deal of speculation as to why, no one knows for sure, and the relevant paperwork has been lost to time.
My take: The Russian round was known as one of the most accurate of its era, and perhaps S&W wanted a "NEW" round for their new large frame DA revolver, but saw no need to reinvent the actual ballistics.