Typical of all of the all-copper Barnes pistol and rifle bullets, the 125-grain XPB loaded by Wilson Combat creates narrower wound cavities than conventional, expanding-hollow-point bullets. However, this bullet—like all Barnes XPB bullets—drives deep. In fact, it penetrated substantially deeper than any non-XPB bullet previously tested. The bullet also expanded to almost 1.7 times its original diameter. This is the most expansion recorded by any previously tested .357 Mag. loads.
| Load | Handgun | MV (fps) | PEN (inches) | EXP (inches) | RW (grains) |
| .357 Mag. Wilson Combat 125-grain XPB | Ruger Blackhawk (4.6-inch barrel) | 1,359 | 19.25 | 0.60 | 125 |
