I'm fascinated. I've shot literally hundreds of animals up to the size kudu with a 180 grain nosler partitions in 300 Win mag loaded to go about 3000 fps. I'm a pathologist so I'm particularly interested in wound channels and bullet failures. I'm known over much of southern African as that 'idiot crawling around bloody carcasses.' Therefore, except in some small animals, where the partition shot thru and thru, I've recovered almost all bullets fired.
I've had exactly one partition bullet failure. The failure was much as you described with loss of mass--primarily lead--in front of the partition. The large majority of the bullets that 'stuck' were mushroomed perfectly under the far side skin. I'm also somewhat an aficionado of the Barnes Triple Shock bullet but have seen a solitary failure here, too. It was a 130 grain, 'store bought' 270. The animal was a 12 point whitetail buck struck in the humerus [mid-shoulder] at about 100 yds. The bone was fractured but the deer ran off and was found two months later one mile and a half away. The slug fell out of the buck's HEAD as I was boiling it out. The front of the bullet was planed backward as if had obliqued off of the humerus or some other hard structure.
So few bullets are absolutely perfect but some bullets--some very expensive bullets--have performed miserably in my hands. We had some perfectly negative experiences in the Zambesi Valley, years ago. I will not mention the bullet because the manufacturer threatened me with a lawsuit if I ever did. Suffice it to say it was a very expensive premium bullet in 375 that weighed more than 280 grains.
And the shotgun comparison. Did you shoot it from the bench? Firing a 12 gauge the way they're usually fired i.e. at a rapidly moving, generally flying, target is definitely NOT the same thing as firing the shotgun from a bench as you would a rifle. The dynamics of your body moving, swinging and PULLING the trigger makes perceived recoil so much less. This goes doubly for the mighty 10 gauge magnum. Sitting down on the bench, pulling the stock tight against your shoulder, aiming carefully and S Q U E E Z I N G the trigger is just a whole lot of fun.
By the way, do you, or anyone else, here, have experience reloading and hunting with Woodleigh bullets?
