
454 Ballistics: Theory and Design of Guns and Ammunition
Then, the total time for the shock pulse is the time between impact and the rarefaction
wave reaching the interface or
shock
ss s=+=0 228 0 196 0 424.[]. [] .[]µµµ
(16.140)
The material velocity behind the rst rarefaction in the yer is found by solving the right-
going Hugoniot in the yer plate for p
2
= 17.453 GPa. So we have
pcuu su u
2012f0
f
=−
0
(16.141)
Inserting some numbers in here we have
−+=
(16.142)
Then,
u
2f
km
=
1 059.
(16.143)
Again u
2f
had to be less than u
1
.
Our next task is to nd the pressure behind the rst rarefaction wave in t ...