The sole other situation which i can imagine is the fact that it may be a normal Model 70 barrel and action by using a substitution XTR inventory. This is often unlikely while...I believe that it's as you describe, an unmarked XTR. You can find an not known connection challenge https://winchestermodel70classicf32112.onesmablog.com/little-known-facts-about-winchester-model-70-xtr-featherweight-value-66987639