Power is a good place to begin and ego is a good place to end when making arguments over handgun caliber. Real-life defensive application is much more mundane: the cartridge must be able to start, to be able to get where it needs to get, and to be maintainable when the hands of the shooter are trying their best to act like the paint shaker.
The same unpleasant truth is indicated by ballistic gelatin work and practice. Other calibers do not perform because they are not harmful, rather, they incur tradeoffs; reliability, penetration, recoil, platform peculiarities that, when combined, begin to pile up quickly with pressure.
1. .22 Long Rifle
22LR is carried due to its ease of firing and easy of finding, however the cartridge suffers an engineering handicap; rimfire priming. That design is intrinsically not as consistent as centerfire, and when you are in a position of defensive, it is a bad place to learn how a misfire is. Terminal performance is frequently a compromise between penetration and expansion that is rarely won by.22 LR short handgun barrels, even when the latter are fired.
The performance of short guns in gel testing includes the following: velocity with barrel length: over a 1.9-inch test barrel in a series of five, there was an average increase of 126 fps, whereas in a series of seven, the increase was an average of 126 fps, with a 4.4-inch test barrel. Such proliferation is important when the ground is already thin.
2. .25 ACP
The reason why 25 ACP exists is that early pocket pistol models required a small centerfire cartridge rather than it being a capable defensive round. The cartridge generally provides low energy and low penetration, and the guns loaded with it tend to enhance the situation with small sights and narrow grips.
Gel testing supports the reputation: in one eight-caliber pocket test battery, the single load of the.25 ACP was the only ammunition to propel all five shots beyond the 11-inch barrier, whereas the overall penetration remained not that impressive in accordance with modern defensive standards. It may be, but it suppresses perfection of conditions, and leaves little room when these become unpleasant.
3. .32 ACP
32 ACP is in that uncomfortable gray place between feeling more serious than.22 or.25, but still not being able to provide consistent expansion and penetration over real world barriers such as clothes. There are loads that are tolerable and those that become a coin toss when they come in contact with fabric.
The second issue which pocket-size .32s are likely to create is the temptation to focus on tiny pistols to the detriment of shootability. The advantage of the caliber, the light recoil, may be swept away by ultra-light platforms which are difficult to hold, difficult to follow, and difficult to shoot in practice.
4. .410 Shotshell Out of Handguns
The attraction is evident: in a revolver, shotgun power. The physics are not so congenial. The dump of short barrels, the distribution of patterns, and the failure of many of the payloads to drive far enough to reach critical targets routinely, particularly when constructing a load around small shot.
More precisely, certain.410 defensive loads are platform-specific. Hornady had a stability issue with the slug in its.410 Critical Defense loading, involving a smoothbore, where the slug tumbled and was very difficult to predict over distance, an accuracy issue, not a vibes issue.
5. .380 ACP (Weakly-loaded out of short barrels)
380 ACP is possible but not as forgiving as most of the carriers want to believe. In pocket pistol types with short barrels, the misplaced load is frequently the source of the mythical failure mode, which is punchy expansion with inadequate penetration, or punched penetration with marginal/no expansion.
Other massive gel programs involving a heavy clothing barrier repeatedly demonstrated.380 to be the weakest of the mainstream defensive calibers that were tested, and comparatively very few loads produced a balanced outcome. It is not necessarily bad, it is just ammo-sensitive in such a manner that new carriers are taken by surprise.
6. 10mm Auto
10mm Auto has real horsepower, which is usually 600 or more ft-lbs under load, and real penalties. The recoil and blast can reduce follow up shots and the deep penetration of cartridge may be a liability in a congested situation where the missed fire and pass through possibilities are punishable.
It is a cartridge containing a definite passage: areas where penetration is the thing. In the case of a normal concealed carry, it makes a manageable defensive issue a recoil management issue.
7. Ultra-Short Barrels.38 Special
38 Special has been able to earn its reputation and snub-nose barrels are a penalty to velocity and velocity is what most hollow points require to expand in a consistent manner. Bullets may act like non-expanding solids in cases of expansion, which simply shoot deep with minimal effort on the target.
Gel test over 2 inch and 4.2 inch revolver barrels underscores the extent to which the performance can change with barrel length, and how frequently the clogging of clothing can upset the expansion process of .38 loads. It does not mean that the cartridge is obsolete; the ultra-short design is challenging.
8. .44 Magnum
44 Magnum is known to generate tremendous energy, usually 1,000 or more ft-lbs and tremendous penetration. Such characteristics are anti-defensive-carry. The muzzle blast and recoil make it difficult to follow-up with accuracy and the size of the platform makes it less portable and difficult to deploy in areas where it is not obvious.
When faced with a defensive situation which demands quick, reliable shots, the caliber becomes too big and the shooter is losing time and accuracy to spend on the capability of firing a ballshot safely when he cannot. The similarity lies not in the fact that a caliber may be deadly. What remains similar is whether it remains dependable, manageable, and predictable when clothing, angles and adrenaline appear out of the blue.
The modern service calibers are more likely to emerge victorious since they have fewer surprises involved particularly when they are loaded with bullets that would yield to the 12 to 18 inch penetration requirement of the FBI. The common definition of best in self-defense engineering sense implies the one that is simplest to operate properly on demand.
