If you are an LE officer, carry a BUG!!!
Many small, easily concealed semi-automatic pistols which are recommended for law enforcement backup or concealed carry use fire .380 ACP or smaller bullets. While these small caliber handgun bullets can produce fatal wounds,they are less likely to produce the rapid incapacitation necessary in law enforcement or self-defense situations.
Handguns chambered in .380 ACP are small, compact, and generally easy to carry. Unfortunately, testing has shown that they offer inadequate performance for self-defense and for law enforcement use whether on duty as a back-up weapon or for off duty carry. The terminal performance of .380 ACP JHP's is often erratic, with inadequate penetration and inconsistent expansion being common problems, while .380 ACP FMJ's offer adequate penetration, but no expansion. All of the .380 ACP JHP loads we have tested, including CorBon, Hornady, Federal, Remington, Speer, and Winchester exhibited inconsistent, unacceptable terminal performance for law enforcement back-up and off duty self-defense use due to inadequate penetration or inadequate expansion. Stick with FMJ for .380 ACP or better yet, don't use it at all. The use of .380 ACP and smaller caliber weapons is really not recommended for LE use and many savvy agencies prohibit them.
While both the .380 ACP and .38 sp can obviously be lethal; the .38 sp is more likely to incapacitate an attacker when used in a BUG role.
BUG--Infrequently used, but when needed, it must be 100% reliable because of the extreme emergency situation the user is dealing with. Generally secreted in pockets, ankle holsters, body armor holsters, etc... Often covered in lint, grime, and gunk. By their very nature, usually applied to the opponent in an up close and personal encounter, many times involving contact shots. A small .38 sp revolver is more reliable in these situations than a small .380 ACP pistol, especially with contact shots or if fired from a pocket.
There have been many reports in the scientific literature, by Dr. Fackler and others, recommending the 158 gr +P LSWCHP as offering adequate performance. Please put this in context for the time that these papers were written in the late 1980's and early 1990's--no denim testing was being performed at that time, no robust expanding JHP's, like the Barnes XPB, Federal Tactical & HST, Speer Gold Dot, or Win Ranger Talon existed. In the proper historical perspective, the 158 gr +P LSWCHP fired out 3-4" barrel revolvers was one of the best rounds available--and it is still a viable choice, as long as you understand its characteristics.
While oversimplified, bare gelatin gives information about best case performance, while 4 layer denim provides data on worst case performance--in reality, the actual performance may be somewhere in between. The four layer denim test is NOT designed to simulate any type of clothing--it is simply an engineering test to assess the ability of a projectile to resist plugging and robustly expand. FWIW, one of the senior engineers at a very respected handgun ammunition manufacturer recently commented that bullets that do well in 4 layer denim testing have invariably worked well in actual officer involved shooting incidents.
With few exceptions, the vast majority of .38 Sp JHP's fail to expand when fired from 2" barrels in the 4 layer denim test. Many of the lighter JHP's demonstrate overexpansion and insufficient penetration in bare gel testing. Also, the harsher recoil of the +P loads in lightweight J-frames tends to minimize practice efforts and decrease accuracy for many officers. The 158 gr +P LSWCHP offers adequate penetration, however in a 2" revolver the 158gr +P LSWCHP does not reliably expand. If it fails to expand, it will produce less wound trauma than a WC. Target wadcutters offer good penetration, cut tissue efficiently, and have relatively mild recoil. With wadcutters harder alloys and sharper leading edges are the way to go. Wadcutters perform exactly the same in both bare and 4 layer denim covered gel when fired from a 2" J-frame.
When faced with too little penetration, as is common with lightweight .38 Sp JHP loads or too much penetration like with the wadcutters, then go with penetration. Agencies around here have used the Winchester 148 gr standard pressure lead target wadcutter (X38SMRP), as well as the Federal (GM38A) version--both work. A sharper edged wadcutter would even be better... Dr. Fackler has written in Fackler ML: "The Full Wadcutter--An Extremely Effective Bullet Design"
, Wound Ballistics Review
. 4(2):6-7, Fall 1999)
Currently, the Speer Gold Dot 135 gr +P JHP, Winchester 130 gr bonded +P JHP (RA38B), and Barnes 110 gr XPB all copper JHP (for ex. in the Corbon DPX loading) offer the most reliable expansion we have seen from a .38 sp 2” BUG; Hornady 110 gr standard pressure and +P Critical Defense loads also offer good performance out of 2" barrel revolvers.
"As a surgeon by profession, I am impressed by bullets with a cutting action (eg. Winchester Talon and Remington Golden Saber). Cutting is many times more efficient at disrupting tissue than the crushing mechanism by which ordinary bullets produce the hole through which they penetrate. The secret to the increased efficiency of the full wadcutter bullet is the cutting action of its sharp circumferential leading edge. Actually, cutting is simply very localized crush; by decreasing the area over which a given force is spread, we can greatly increase the magnitude to the amount of force delivered per unit are--which is a fancy way of saying that sharp knives cut a lot better than dull ones. As a result, the calculation of forces on tissue during penetration underestimate the true effectiveness of the wadcutter bullet relative to other shapes."
Any of the Airweight J-frames are fine for BUG use. The steel J-frames are a bit too heavy for comfortable all day wear on the ankle, body armor, or in a pocket. My current J-frames are 342's and previously in my career I have used the 37, 38, 649, and 642. I like the 342 w/Lasergrips very much. Shooting is not too bad with standard pressure wadcutters and the 110 gr DPX, but not so comfortable with the Speer 135 gr JHP +P Gold Dots. Before the advent of the 110 gr Corbon DPX load, I used to carry standard pressure wadcutters in my J-frames with Gold Dot 135 gr +P JHP's in speed strips for re-loads, as the flat front wadcutters were hard to reload with under stress. There is no reason to go with .357 mag in a J-frame, as the significantly larger muzzle blast and flash, and harsher recoil of the .357 Magnum does not result in substantially improved terminal performance compared to the more controllable .38 Special bullets when fired from 2” barrels.
For years, J-frames were considered "arm's reach" weapons, that is until CTC Lasergrips were added. With the mild recoil of target wadcutters, officers are actually practicing with their BUG's; when combined with Lasergrips, qualification scores with J-frames have dramatically increased. Now 5 shots rapid-fire in a 6" circle at 25 yds is not uncommon--kind of mind blowing watching officers who could not hit the target at 25 yds with a J-frame suddenly qualify with all shots in the black…
2" J-frames are great BUG's and marginally acceptable low threat carry guns because they are lightweight, reliable, and offer acceptable terminal performance at close range--downsides are difficulty in shooting well at longer ranges because of sight design and sight radius limitations, along with reduced capacity coupled with slower reloading. Nonetheless, with the addition of CTC Laser Grips and an enclosed or shrouded hammer, the 2" J-frame models without key locks (I personally will NEVER own firearm with an integral lock)
may be the best BUG's and most reliable pocket handguns available.
Another great BUG option if it can be comfortably carried, is a compact 3-3.5" barrel 9 mm pistol like the G26, S&W M&P9c, Walther PPS, HK P2000SK, Kahr PM9, S&W Shield, Sig P239, or S&W 3913, as these offer superior terminal performance compared to either .380 ACP or .38 Sp handguns. A subcompact BUG (like the G26) is particularly nice if it can use the same magazines as the primary full size pistol (like a G17/19).
As always, don't get too wrapped in the nuances of ammunition terminal performance. Spend your time and money on developing a warrior mindset, training, practice, and more training.