After years in search and rescue, I’ve come to love tracking. However, it’s a stressful process trying to find an animal that you’ve worked so hard for.
If it was a double lung but high, it will take time to fill the lungs to the point where you get blood coming from the entrance hole. This is especially true when it’s not a pass through because it can create a seal and can be compounded further by fat or tissue.
If it was lethal, I’m guessing he’s under 300 yards from where you shot him. Square off 300 yds using your phone or paces and grid it. I would start on the far side of the 300 and work your way back— this is based on the notion that he likely went more than 100yds but less than 300. Once you find his track, study it. Measure it. Make a marking stick that you can use to measure his track length from one to another. Use sticks or flagging to get a direction of travel. This is super helpful when you look back on the track. When you know exactly where he stepped you will find more blood. Even if minuscule, you will find more blood than you originally thought.
you’re obviously an experienced hunter and probably know all of the above. But good lung hits don’t always produce much blood. They are often fatal. Best of luck in finding him and kept us posted!