The apparatus compensates for equipment errors that prevent {HEAD ~ a marksmanship device} from providing {TAIL ~ an accurate indication} of a firearm hit or miss 
The apparatus compensates for equipment errors that prevent { HEAD ~ a marksmanship device } from providing { TAIL ~ an accurate indication } of a firearm hit or miss
OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH