I'm doing this JUST in case someone wants to calculate a feat like this
This only will apply if the "victim" is a regular human... for obvious reasons
The average volume of a human head is 2912 cm³, so keep that in mind and the density is like 0.8072 g/cm^3 https://uk.answers.yahoo.com/question/index?qid=20131021012233AA77BBE http://www.answers.com/Q/What_is_the_density_of_an_adult_human_head?o=37866&l=dir&qsrc=990&qo=questionPageSearchBox&ad=dirN&ap=reference.com
There are remains of the head[]
Fragmentation: 4.4 J/cc
The feat will at least get a value of:
4.4 x 2912 = 12812.8 joules
There are very few remains of the head[]
Violent fragmentation: 7.533 J/cc
7.54 x 2912 = 21956.48 joules
The head is not there at all[]
Pulverization: 12.9 J/cc
12.9 x 2912 = 37564.8 joules
So, at least like Wall level...