The initial testing of EFOC/UEFOC effect on the Heavy Bone Threshold showed no effect on the bone-breaching rate. However, when compared to matched-set arrows of normal/high FOC they DID show a very marked increase it the total outcome penetration in all instances where the arrow did breach the bone (with arrow sets both above and below 650 grains total mass). They DID NOT show any increase in the bone-breaching rate in all matched-set testing of the Heavy Bone Threshold with arrows having below-threshold mass (below 650 grains total weight). Above threshold weight all sets tested showed a 100% bone-breaching rate, regardless of the degree of FOC.

I must note that this testing was done during the last year I was able to do testing. Though the data is limited the frequency and magnitude of the increase in post-breaching penetration demonstrated was easily sufficient to say that having EFOC/UEFOC is a great benefit once the bone is breached.

There are a number of folks who are hunting with arrows in the range of 31% to 32% FOC, and a few using slightly higher FOC. That, of course, does not take into account those natives in Papua New Guinea who are using arrows all the way up to well over 40% FOC.

Ed