Loads for Full-Sized .38 Revolvers With 4" or Longer Barrels: The Numero Uno .38 Special defense load for your 4" barrel revolver is the Cor-Bon .38 Special+P 125 grain JHP. It is a very high-pressure load and should be used only in modern six-shot revolvers. It has less felt recoil and muzzle flip than the #2 choice, which follows. When I carry a 4" .38, I want it loaded with this cartridge.
The second-best choice is the .38 Special +P 158 grain lead semi-wadcutter hollowpoint (LSWCHP) available from Federal, CCI, Winchester and Remington. Ayoob has found the latter to have the greatest expansion, so I would choose Remington (catalog #R38S12). This unjacketed all-lead round (often called the "FBI load" or "Chicago load") is a proven manstopper when fired from a 4" barrel. Your fixed-sight .38 revolver it will usually shoot to point-of-aim with this load; lighter bullets will normally shoot low (some very low). All fixed-sight .38s are regulated at the factory to shoot accurately with standard velocity 158 grain bullets, as this was the weight of the long-time standard American and Canadian police load.
* Federal makes the FBI load in their Nyclad line covered with a thin Nylon jacket to prevent leading (#P38G). This is now a police only load. The all-lead version is #38G.
* CCI offers the famous FBI load in their economical aluminum-cased Blazer line (#3523). This is a bargain. What I really recommend, however, is that for practice you use the CCI Blazer 158 grain JACKETED hollowpoint (#3526) because it duplicates the ballistics and recoil of the FBI load without fouling your barrel with hard-to-scrub-out lead deposits. These are a bitch to clean (I use 'Flitz' metal polish with good results. It will also remove unsightly "burn rings" from the cylinder face of your stainless-steel revolver).
Note: .38 Special ammunition is loaded to two pressure levels: standard pressure and +P. Standard pressure loads may be used in any .38 Special revolver, but +P loads should be fired extensively only in steel-frame .38 Special revolvers. Firing a few (under fifty) +P loads in your aluminum-framed .38 Special revolver will not destroy it or cause it to explode, but will damage your aluminum-framed revolver if you fire more than a hundred rounds. The main problem with carrying +P .38 Special loads in an aluminum-framed .38 Special revolver is that the kick is nasty and slows repeat shots. Thus I recommend standard pressure ammunition for aluminum-framed .38 Special revolvers, as it is much easier to score fast hits.
Other .38 Special Loads for Your 4" Barrel Revolver:
IMI-Samson also offers a lightweight, very high pressure load, the 110 gr. +P+ JHP. This is said to be a ballistic duplicate of the law-enforcement-only "Treasury" load that T-men used to carry. Who cares? The Cor-Bon 125 gr. +P load is superior. And never use any 147 grain bullet in any caliber. They are cursed.
All major manufacturers catalog light .38 +P hollowpoints, from 95-129 grains. None of these are as successful as the Cor-Bon .38 Special +P 125 grain JHP or 158 grain +P LSWCHP, so why carry them? Light +P loads only make sense in a 2" barrel snub (more on this later). The Federal Hydra-shok and Winchester Silvertip may look cool, but the boring-looking Cor-Bon and FBI loads do the job in a 4" revolver. Stick with them.
PMC makes a bizarre 66 grain tubular hollow bullet load. Some enthusiastic gun-shop salesman may try to sell it to you. Refuse politely. Also avoid the Remington 95 grain +P SJHP (R38S1) due to inadequate penetration.
The Glaser Safety Slug is a good choice for self-defense in a .38 revolver of any barrel length (see caveats under "exotic ammunition," above). It is crucial to keep the chambers and frame interior absolutely free of oil or solvents when carrying Glasers, as you don't want any Breakfree CLP or Hoppe's #9 solvent seeping into the primer pocket and deactivating the round. This is important for all rounds, of course, but the Glaser isn't known for particularly good sealing against such mishaps. You may also want to consider carrying two Glasers as the first rounds to be fired, and JHP loads for the rest. This gives you a bit of insurance if your assailant tucks himself behind a sheet rock wall or doorway or some other flimsy cover that JHP rounds can blast through.
A Special Note on Snub-Nose .38 Revolvers With 2" or 3" Barrels: The Cor-Bon .38 Special +P 125 grain JHP and 158 grain LSWCHP FBI load are not the best choice for 2" or 3" barrel revolvers. The short barrel does not provide enough velocity to ensure reliable expansion with these load, and the unpleasant and hard-to-control recoil hurts snub-nose accuracy (as well as your hand). Controllability is crucial, and I recommend non +P standard pressure loads, for the .38 snub-nose.
Good +P choices for a steel-frame 2" .38 snub-nose revolver are:
* Federal 125 grain +P Nyclad LSWHP (P38N) - my preferred .38 2" barrel snub-nose revolver load (a.k.a. the "Chief's Special" load, now available only to the police).
* Federal 129 grain +P Hydra-shok JHP (P38HS1)
* Remington 125 grain +P Golden Saber HPJ (GS38SB)
* Cor-Bon 110 grain +P JHP - I would recommend this high-pressure load only for the sturdy (and heavy) Ruger SP101 snub-nose .38 or .357 Magnum revolver.
Standard Pressure (non +P) Loads.
If you carry an aluminum-frame snub nose .38 (e.g. S&W Model 38 Bodyguard, 642, 442, 37, or Colt Cobra) I urge you to carry a standard pressure (non +P) .38 round. The best standard pressure .38 load is the Federal 125 grain Nyclad lead hollowpoint (P38M). This P38M hollowpoint - known as the "Chief's Special load" - was specifically designed to expand at lower velocities and is the industry leader in standard pressure .38 rounds. This load is now available to police departments only.
Another acceptable standard pressure .38 load is the Winchester Silvertip 110 grain JHP (X38S9HP). A third possibility is the Federal Low Recoil Personal Defense 110 grain Hydra-Shok JHP load (PD38HS3 H)
Note well: if you have a J-frame Smith & Wesson snub-nose .38 (i.e. the five-shot Model 36/37 Chief's Special, Model 38/49/649 Bodyguard, the 640/642/442/940 Centennial) you can greatly improve the controllability of your gun by installing Uncle Mike's "Boot Grip." This is a $14 godsend. The skinny little wooden grips that come on these guns are worthless. Installing good grips does wonders for your ability to control your .38 snub-nose revolver in rapid fire for more hits.