You need to stay on his path. If lost blood look for his track, a buck that size should have a good sized track. Also make sure he didn't cut back on you. I have yet to track a wounded buck over a long distance that didn't make a severe cutback at some point. I once tracked a buck in a over grown logged woods. He was running a trail, which was the only wayto get through the shoulder high briars. He stepped over a log, and turned left, right through the thickest above head high briars I've ever seen. They will do some amazing things.