If we can’t meet the minimum threshold for cavity pressure, then the hollowpoint won’t open up and the slug’s ability to create damage along the wound track will be reduced, by virtue of its smaller frontal area. Bad things can also happen if the pressure exceeds design values, but we won’t concern ourselves with that now-the most critical extreme, for our purposes, occurs on the low end. If the minimum threshold is not met, then the pressure within the hollowpoint cavity will not be sufficient to initiate and promote expansion. The key here is that a certain energy threshold must be reached to begin this expansion. The skives cut into the core and jacket of this bullet control how the bullet will expand. If the bullet cavity is not pre-stressed, then the soft lead walls will ideally curl back and the final bullet shape will resemble a mushroom cap, of sorts. If the bullet is pre-stressed with cuts in the cavity walls and jacket (called “skives”), the bullet will ideally open up along those fault lines and the final bullet shape will resemble a flower with multiple petals radiating out from the core. The mechanical or hydraulic forces which build up inside the cavity exert outward pressure on the inner walls of the cavity, and force the bullet to open up, or expand. To explain, hollowpoint bullets are designed to expand by virtue of the pressure that is generated inside their hollow nose cavity. That may not sound like much, but the difference can have a very significant effect on the terminal ballistics of a hollowpoint handgun bullet, because it can take the bullet outside of its designed “operating window.” Flowers and Fungi We know that some individual guns are “faster” or “slower” than their peers, based on variables like barrel-cylinder gap or bore dimensions, but in general the difference between a 1.875” barrel on a Smith & Wesson 642 and a 4” barrel on a Smith & Wesson 686 can account for about 75-150 feet/second (fps) of velocity, and at about 40-80 foot-pounds (ft-lbs) of energy in a cartridge like the. The service-length guns, with their four-inch and longer barrels, can generate more velocity and energy with the same cartridge than the shorter snubs do. The nominal two-inch barrel that hangs off the end of most snubs helps to make the gun disappear nicely in a waistband, pocket, or ankle holster, but it also exacts a penalty on bullet velocity and energy. Unfortunately, the main feature that makes the snubby so attractive as a carry gun is the same that robs the gun of some of its power. While a medium or medium-large frame revolver is still an incredibly effective gun for self-defense inside and outside the home, it’s the smaller “snubby” that gets called on the most for concealed carry and law enforcement backup needs. If you’re like most shooters these days, your interest in the revolver as a defensive weapon centers around small frame guns that are easily carried and concealed.
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