Sierra Bullets 223/bolt:
"Unlike most of the currently available semi-autos, factory bolt-actions generally come equipped with 1x12" twist barrels. As such, they can handle
Sierra’s line of bullets from 40 to 60 or 63 grains, but not the heavier
MatchKing designs. This isn’t a problem in custom-built rifles, if the shooter
chooses a twist rate appropriate for the bullets used. With this cartridge, we
recommend a 1x10" as minimum for the 69 grain MatchKing, and a 1x8" for
77 or 80 grain MatchKings."
I love those Sierra articles, one for each gun type, of the same cartridge. I wish they did that for 308, too. The loads they publish for bolt guns are 100-200 fps faster, mainly due to barrel length. Curiously, the specific powder loads, for the same bullet weight class, are different from the AR loads to the bolt gun loads!!
Savage makes their current 223 bolt guns in 1:9". I also have a Ruger Mini-14 that is 1:7"; not all of them are - they have used 3 different twist rates, I believe.
Not understanding the twist rate of the gun you shoot, and the bullet weight you use, is probably responsible for at least 2/3 of the people who say a particular 223 isn't accurate.