I also am interested in the concept of frangible bullets especially as they could be adapted to varminting.
If you are interested I'd like to do a test for a magazine article in POINTBLANK magazine.
I don't have a .50 but I do have a couple of .30 cals, a .243 and access to a .224 long-range varminting rig.
I am also in the middle of testing a short-range coyote rifle using the 7.62x39 case with a .308 barrel. Your frangible bullets would be perfect for this rig because velocities can be a bit low when the range stretches much beyond 200 yds.
I have used the 110gr VMAX in this rifle with excellent results.
You can see some of my experiments at
or see previous copies of POINTBLANK magazine at
Editor - Pointblank