Quote Originally Posted by ABNAK View Post
Can someone explain to me why a .308 is okay with a 16" barrel but a 6.5 Creedmore needs a longer one for better performance (like 18" or greater)? I mean a 6.5C is basically a necked-down .308, so it isn't like case capacity is considerably different.
Its not. its basically an old wives tale that lives on where a 308 HAD to have a 20 inch barrel to be effective, only now its 6.5cm HAS to have a long barrel to do well. All barrels can do better with a longer barrel but there becomes a point where is a longer barrel practically if you are only shooting to say 800

a short 13.5 to 14.5 will launch a 178 ELDM at around 2450fps to around 900 Yards with about 2.5 mils(79 inches) of wind at 10mph
a short 14.5 to 16 inch will launch a 147 ELDM at around 2450 to around 1100 and at 900 yards has 1.8 mils(58 inches) of wind at 10mph

at 900 yards, a short 6.5 will have almost one less human wind drift than a short 308

a typical 20 inch 6.5 will launch a 147 ELDM at around 2600fps to around 1300 and at 900 yards, has around 1.6 Mils(51 inches) of wind at 10mph

Just with everything else, there are trade offs, I used to be all about longer barrels, but as bullets have gotten more efficient, I came to the conclusion that shorter barrels make more sense for me.