I will post pictures of the recovered fragments later -- and I realize that it's completely unscientific, but the copper jackets completely separated from the lead -- I haven't seen that happen before in years of shooting at this particular mud bank...

Has erosion increased the percentage of rock in that dirt over the years?

I have seen the old Hornady RNSP .458/500gr completely separate jacket from core at 2100 fps on a cow moose chest shot, hitting only a rib and lungs going in.

The jacket and two chunks of lead core broke three ribs on the off side though, each of the total of three fragments breaking one rib each as they came to rest, no exit wound.
The moose flopped over dead right there. It was a most spectacular bullet failure.

No, it's pretty much dirt -- made when a field was leveled to raise crops. It made a pretty deep hole, etc, but the copper seems to have barely any lead residue on it, just like it popped apart.

O.K., dirt/soil/clay/sand is very tough on a "cup and core" bullet. We would expect one of those non-bonded ones to come apart completely if impact velocity is high enough. Not surprising.
What make of bullet was it, at what velocity?

As long as the dirt bank died, your bullets did not fail . . .

It's the hornady factory loads -- they were the cheapest form of 375R ammo available to me. I just bought them for plinking, so they did fine... I might use them on a white tail/axis/black buck or two, I just didn't think they'd fail that badly -- I've had other bullets flatten out completely/seriously deform from other guns, but they never came apart like that.

As far as velocity, it's the factory load from an Alaskan at either 50 yards, or 100 -- I was sighting my rifle in.

I’ve had Interlocks come completely apart at close range when fired @ H&H velocities…

Never used Interbonds, though I have a couple hundred for my 458s…

Not very surprising results to me…

Hornady bullets are best left to thin skinned game…

Anything tougher (like dirt banks ) you need to step up to a premium bullet…

Matt V.

Dirt banks are tough. I have seen them take thousands of rounds and remain standing. Must be the mineral content.

I have posted this photo before, but apropos of this subject, here are what was left of two .510" 600 grain Woodleigh PP softs after being fired into a dirt bank at 2,500 fps.



Note that they are bonded core bullets and that they expanded all the way back to the bases but still held together.

Failure in dirt and failure in a animal are two different things. Rip is right “dirt/soil/clay/sand is very tough on a "cup and core" bullet.†They may work great on game. I would go to a bonded bullet for all my hunting just because I like the insurance of a premium bullet. But as long as the dirt bag or was that dirt bank died quickly in a humane way………
Bill