Good Question.I know is the Indian Army is currently using the Sigma navigation system and it has been proven in combat on a Caesar 155 mm gun. NATO uses the navigation system on the Mars multiple rocket system.
I’m thinking in terms of mils and meters and MTBF, A-sub-oh and those things.
With longer range comes a desire for improved pointing accuracy, measured in mils. (A mil is the angle subtended by one meter at on kilometer, about a milliradian.)
Russian short range artillery rockets are notoriously inaccurate, so worry about were you aimed the damned thing in the first place would imply improved accuracy.