fns-9 ls front sight

Hi, New here. I have 3 FNS-9s. Two Identical FNS-9 LS (very close ser#s) and one FNS-9 (standard size). The FNS-9 standard shoots very well and the POA / POI is as close as you could ask for with fixed sight. Very Nice and spot on. Both the FNS-9 LSs POA and POI differ about 12", shooting...