Shots to the Central Nervous System (CNS) at the level of the cervical spine (neck) or above, are the only means to reliably cause immediate incapacitation. In this case, any of the calibers commonly used in law enforcement, regardless of expansion, would suffice for obvious reasons. Other than shots to the CNS, the most reliable means for affecting rapid incapacitation is by placing shots to large vital organs thus causing rapid blood loss. Simply stated, shot placement is the most critical component to achieving either method of incapacitation.
Cartridge and caliber discussions are even more annoying and useless than tactical pontifications. For both tactical and hunting environments, most claims of firearm/cartridge ineffectiveness is usually the operator’s fault. Lousy marksmen on the range experiencing their first stressful shooting experience at an enemy or at big game shoot even worse in the field and then place blame for their failure on perfectly adequate equipment.
A solid hit might still not be an instant death ray, but most shots are not accurately directed. Those poor range results should have been the first indicator, but too many fools lull themselves into believing low scores won’t impact performance elsewhere. Worse, most don’t even bother to measure.
Shot placement is paramount and law enforcement officers on average strike an adversary with only 20 – 30 percent of the shots fired during a shooting incident. Given the reality that shot placement is paramount (and difficult to achieve given the myriad of variables present in a deadly force encounter) in obtaining effective incapacitation, the caliber used must maximize the likelihood of hitting vital organs.
The Ballistic Research Facility has conducted a test which compares similar sized Glock pistols in both .40 S&W and 9mm calibers, to determine if more accurate and faster hits are achievable with one versus the other. To date, the majority of the study participants have shot more quickly and more accurately with 9mm caliber Glock pistols. The 9mm provides struggling shooters the best chance of success while improving the speed and accuracy of the most skilled shooters.
Getting hit rates up starts on the range. Beyond novice stages, merely hitting silhouettes isn’t good enough. Unless increasingly-challenging time limits are enforced, getting center chest hits on static, fighting-distance targets isn’t good enough either.
We can argue on how best to hold the gun, or use the sights, or conduct the training but none of that matters if trainees aren’t require to demonstrate increasing proficiency. That requires the means to measure skill and the requirement to demonstrate that skills are increasing over time.
Morons complain a range drill like El Presidente isn’t realistic for police/CCW, but fail to define what should be done instead. The point is developing the means to get hits fast and providing a definition to what that means. A par El Presidente (all center chest hits in 10 seconds with duty gear) is a good step in that direction. Or use something else. Course specifics are less important than providing a skill metric and enforcing it.
If you can’t do it on a square range, then you can’t do it.