Re: To 5R or not to 5R
There's a school of thought that a barrel with an odd number of lands/grooves will shoot better at long distances due to less distortion of the bullet.
In barrels with an even number, lands are always 180 degrees apart and cause more "pinch" of the bullet while the odd numbered barrels have the bore directly opposite each land resulting in 1/4 the distortion. Is also supposed to result in less gas leakage.
Someone out there on another forum or barrel maker site posted a diagram explaining this but I lost track of it.