Every now and then you will come a cross a story where an animal that was hit well ran off a little way. Sometimes critters do that. Not sure why, but they run when they're supposed to be dead. Maybe it's adrenaline? Sounds to me like the bullet did what it was supposed to... penetrate, cause internal damage and exit.
You will get less DRT's with controlled expansion bullets because they are designed to retain mass, and penetrate and therefore do not cause a lot of collateral internal damage. I've killed maybe 30 deer, antelope and a large bull elk and bighorn sheep with 7mm 160 gr partitions. Few were DRT's, most went a few steps and fell over, some wandered a little farther but none more than 20 yards. Exit holes were about the size of a nickel to a quarter.
Partitions have been reported to come apart at higher velocities, like maybe 3000 fps +. The A-Frame design has a thicker cross member (partition) and a sealed tail which makes them much tougher than Partitions.
Frangible bullets, like Bergers which basically grenade inside the animal cause massive amounts of internal damage and will put animals down quicker, on average, than controlled expansion bullets, provided they are used correctly, i.e, heavy for cal with lower MV's and placed in the vitals.
ABLR's and Bergers re both frangible bullets. The difference is, the ABLR with its tip and thin nose jacket is designed to expand at lower velocites. At close range, high velocity, they explode on contact. Bergers on the other hand penetrate a couple inches or so and then explode inside the animal, provided they aren't driven at uber velocities.
