Brass Fetcher Ballistic Testing
Scaling Penetration Depth from Clear Ballistics Gelatin to 10% Ballistic Gelatin
Clear Ballistics ballistic gelatin offers several attractive usability features when compared with porcine gelatin. It does not require refrigeration and can be purchased in a ready-to-shoot configuration. Visual clarity on Clear Ballistics gelatin blocks exceeds that of most porcine ballistic gelatin.
There are two flow regimes associated with bullet penetration of a fluid medium, commonly referred to as the high velocity flow regime and the low velocity flow regime. For a given projectile, the major determinant of penetration and expansion in the high velocity regime is the density of the fluid. The fluid drag equation is given below:
FD = fluid drag force
P = density of the fluid
v = velocity of the projectile
Cd = drag coefficient
A = projected surface area of projectile
Clear Ballistics 10% synthetic gelatin had a density measurement of 790 kg/m³ while 10% porcine gelatin has a density of 1034 kg/m³. Based on density alone, it is conceivable that differences in terminal performance may be noticed when shooting Clear Ballistics 10% synthetic gelatin and 10% nominal porcine gelatin. To test this, we shot 20 shot samples of SIG Sauer V-Crown 9mm Luger 115gr JHP and 40 S&W 180gr JHP into new bare Clear Ballistics synthetic gelatin and bare nominal 10% ballistic gelatin. The 9mm Luger V-Crown 115gr is designed for short barrel firearms and the test gun for this report had a 4.4" full-length barrel. As such, results seen in this report are from a higher-than-designed velocity, which can be expected to give abnormally shallow penetration depths and slightly greater expansion. The 40 S&W V-Crown 180gr load was chosen because it represents the heaviest common bullet weight in 40 S&W.
It is reasonable when shooting 9mm diameter JHPs near this velocity to multiply the depth measured in Clear Ballistics gelatin by 0.819 to obtain the depth expectable in nominal 10% porcine ballistic gelatin.
It is reasonable when shooting 0.400” JHPs near this velocity to multiply the depth measured in Clear Ballistics gelatin by 0.753 to obtain the depth expectable in nominal 10% porcine ballistic gelatin.