Last week I posted an image that showed two blocks of SIM-TEST media that had been recast and were ready for ballistics testing use. In that post I asked for some reader input on future testing candidates. One long time blog reader and I share a common interest in the Kel-Tec P-32. The diminutive P-32 is a true pocket pistol that is so small, light, and flat that it simply disappears in the pocket even when carried in a decent pocket holster. Eric asked me to do some tests with the .32 ACP and I was happy to oblige because this same testing had been on my radar for months.
I was surprised that even in the full daylight, I was able to use the LaserLyte to help with my aiming of the test shots. The primary reason for purchasing and installing the laser was to help me accurately shoot test shots like these and this was my first chance to use the laser in full light. At the distanced I needed it, it worked great.
Many months ago I did a study on the .32 ACP and .32 NAA cartridges. At that time I was simply running rounds over a chronograph to capture their speed and calculating their muzzle energy. I had started investigating some terminal ballistics testing so from the previous testing I knew that the CORBON .32 was a decent expander and I also knew that the Fiocchi Extrema was the next fastest JHP available so it should also expand. The previous ammo study can be found HERE.
With my previously gained knowledge on the CORBON and Fiocchi loads, I decided to test these two head to head in the same block of SIM-TEST. The video below documents the full test from the range through bullet recovery. Both loads where shot through two layers of loose medium weight denim and into a SIM-TEST block that approximates the density of 10% ballistics gelatin.
The final results were a bit surprising in some aspects and expected in others. Let's review the detailed data captured from testing. On the top line, I was pleased to see that both loads did expand in the test. The two loads did demonstrate large variances in the amounts of expansion and penetration. Weight retention was excellent on both tested rounds. I'll recap each load individually below.
Fiocchi Extrema 60 grain XTP
The Fiocchi Extrema line uses the Hornady XTP bullet in place of the JHP bullet used in the Fiocchi Shooting Dynamics line of ammunition. From previous testing, I knew the Extrema line is loaded "hotter" than the Shooting Dynamics line. My gut feeling told me that this loading had a high probability of demonstrating at least some expansion. I was pleased to see that my gut was right and the recovered round did expand even after penetrating two layers of denim. The surprise came when measuring the penetration depth. 11 inches of penetration is really quite remarkable from this little 60 grain slug. The load demonstrated a great balance of penetration depth with some modest expansion.
CORBON 60 Grain JHP
From previous tests, I knew that the CORBON was a real screamer in the velocity department. No other round previously tested comes close to the velocity and subsequent calculated ft/lbs of energy of this CORBON loading. I also had the expectation of massive expansion from this load and the CORBON again delivered on that expectation. The recovered bullet exceeded 1/2 an inch in size. That's really incredible and on par with many loads in .380 AUTO and even some 9mm loads I've previously tested. The tradeoff for this massive expansion comes at the cost of penetration. Regardless of initial velocity, the wasn't enough speed and mass to push this round for deeper penetration.
Final Wrap-Up & My Thoughts
With this test we have a classic example of expansion vs. penetration. The Fiocchi load has a fine balance of both expansion and penetration that allows it's moderately expanded XTP bullet to reach a full 11 inches of penetration depth. The CORBON load is built for speed and expansion. It trades off penetration depth for it's caliber leading expansion. The fact that both loads exhibited expansion in terminal testing may end up being the key learning from this test. Many folks just don't believe that any JHP load will expand due to their slow velocities. These two loads demonstrate that isn't always the case.
I'd like to thanks Steve T. for his very generous contribution to help fund testing like this and also keep the blog up and running. I really appreciate the support Steve.
If anyone else would like to contribute, you can always use the Fund More Research tab at the top of the blog or just click HERE.