Re: Picking up a new .243
In my experience, heavy barrels tend to be more consistent over longer shot strings.
Heavier rifles are also easier to keep steady for precision shooting.
But, you may also give up some maneuverability. Plus, they can be a burden to carry for long hikes.
I would go heavy if long range is the main objective.
Also, you'll want an 1:8" twist if you want to take advantage of the 243 for long range with the high BC 105-107 grain bullets.
If you really want to see what it can do with the 115's, you need a 1:7.5" twist.