The one other state of affairs that I can visualize is always that it may be a standard Model 70 barrel and action by using a alternative XTR inventory. This is certainly not likely nevertheless...I think that it is as you describe, an unmarked XTR. Cartridges are properly fed into https://cruzoxxwt.tinyblogging.com/a-secret-weapon-for-winchester-model-70-classic-featherweight-70514420