Re :
2 solutions :
1) change the range from 208 to 160 or 164 (not a great difference
)
2) add a new unit EFFS ER or MO 120 RT-F1 ER with the 13000 m (260 hexes
) range. On the other hand you need to reduce the accuracy or ROF because the RAP ammo was not really accurate for arty standards used in french artillery. In 1992 the maximum error allowed was 1 m for 1km.
The ER mean Extended Range off course.