I bought a pawn-shop gem, a somewhat rare Winchester 77, 15-round, tube-feeder (wonderful to me, anyway). Very nice, very accurate. But my model does not have a bolt-hold-open after the last round. Unless I count every round, every time, I sometimes dry-fire it after the tube is empty. I thought placing a .22 snap cap in the tube as a 15th round would at least prevent the firing pin dry-firing and avoid damage. Comments? Ideas? Where is the best place to find a user's manual? Thanks in advance. Photos later once I refurb the walnut stock.