I found this op's findings and Metcalf's interesting . Metcalf's article was a great read. Thought I would share.
Rather than cut and paste I will just share the link.
http://www.scoutrifle.org/index.php?topic=647.0;wap1Shooting times article mentioned in post here - by Dick Metcalf • January 3, 2011
http://www.shootingtimes.com/2011/01/03/longgun_reviews_scout_102606/Metcalfs findings - (excerpt)
The 16.5-inch Compact and Frontier rifles are 31 percent shorter. How much does that reduce their ballistic performance? Another short answer: not enough to even consider.
For example, the nominal manufacturer’s velocity specification for Winchester’s Supreme 7mm-08 140-grain Ballistic Silvertip load through a 24-inch test barrel is 2770 fps. I chronographed that load through my review sample 16.5-inch 7mm-08 Ruger Model 77 Compact; the result was an average 2647 fps. That is 95.5 percent of the nominal velocity. And the standard deviation round to round in that average was only 10 fps. .......... The same holds true for the other chamberings currently available in the Model 77 Compact and Frontier.