Requires 500 Weapon Skill Points in order to activate the latent effect. Same with the other R/E weapons from KSNMs that have a similar effect.
1 weapon skill point for a solo WS, or opening any SC
2 points for closing a Level 1 SC (Impaction, Liquefaction, Transfixion, Detonation, Scission, Reverberation, Compression, Induration)
3 points for closing a Level 2 SC (Fusion, Fragmentation, Gravitation, Distortion)
5 points for closing a Level 3 SC (Darkness, Light)