I've been looking for this type of data recently and this came up. If this is already posted I apologize-I did a search for it but no luck. This is fascinating-they cut encore barrels down 1" at a time to see changes in velocity.



http://www.ballisticsbytheinch.com/index.html

http://ballisticsbytheinch.wordpress.com/

Good info, but they need to do some of the bottlenecks 'cause they are affected much more by barrel length than the shorties.

interesting...