I have also heard more accurate but at what range,between my 300 WSM and my 300 Ultra mags,the diffrence I could not tell under normal hunting conditions or off the bench shooting side by side out to 400 yds,when you have a miles of stubble feild behind your house I shot both to see how far they would go befor they hit dirt and tell you what,they went farther than I can kill anyting accurately.

As for short vs long,there is probaly some truth due to better groups to a more solid action and less metal to flex under presure.

BBJ