Cartridge Overall Length
Also: OAL · COAL
Total length of a loaded cartridge from the base of the case to the tip of the bullet. Constrained by magazine length and by how the bullet sits relative to the rifling.
OAL matters for two reasons. First, it has to fit your magazine — too long and the round won’t feed. Second, it determines how close the bullet sits to the lands of the rifling. Closer is generally more accurate; too close raises pressure.
OAL is less repeatable than CBTO across lots because bullet tips can vary. For load development, measure CBTO.