One of the biggest complaints I hear and read by “bear guides” during the recovery phase is “lack of a blood trail” on a supposedly lung shot bear.

Bear fat, experts suggest, can often plug the exit hole if the exit hole is small and dense bear hair can absorb blood as well. Exit hole size on exit can aid in blood flow if the hole is large enough. Energy to penetrate and exit is equally important. Bullet caliber?

Bigger bores work but you also need penetration. 

Are we missing more here? What about the bullets construction?

What about the sectional density of the bullet? Is the bullet monolithic copper, standard cup and core, is it bonded, or is it partition/A-Frame?

Terminal ballistics tell the story here. Both bonded, partition, and monolithic bullets lead-the-pack in penetration. Cup and core, jacketed lead works but tend to separate thus penetration is often less in big game such as elk, moose and bear but cost much less. I have used both monolithic copper, bonded and partition/a-frame more than typical cup and core styles. They do cost more but I’m a good, better, best kind of hunter. Often seeking the best in bullets. 

My recent Maine bear was hit with a 7mm 160g Nosler Partition In the shoulder at 3000 fps.

The internal damage was devastating and left a 2 inch wide tunnel on entering the shoulder, wrecked the lungs,exited and left an immediate blood trail for just 25 yards where we found the bear piled up. 

The bullet mushrooms extremely well and the rear core remains intact for deep penetration and often exits. 

The Nosler Accubond is one of the worlds best bonded and accurate bullets but Nosler says the Partition bullet is best on penetration for an exit wound. 

And they were right! The Nosler Partition did the job very well. Go Nosler!

Good Hunting!