Editing Terminal ballistics (section)

=====Expanding=====
More effective on lighter targets are expanding bullets, the [[hollow-point bullet]], and the [[soft-point bullet]]. These are designed to use the hydraulic pressure of muscle tissue to expand the bullet. The hollow point peels back into several connected pieces (sometimes referred to as petals due to their appearance) causing the bullet to create a larger area of permanent damage. The hollow point fills with body tissue and fluids on impact, then expands as the bullet continues to have matter pushed into it. This process is informally called mushrooming, as the ideal result is a shape that resembles a [[mushroom]]&mdash;a cylindrical base, topped with a wide surface where the tip of the bullet has peeled back to expose more area while traveling through a body. For the purposes of aerodynamic efficiency, due to the hollow-point not creating drag, the tip of the hollow-point will often be tipped with a pointed polymer 'nose' which may also aid in expansion by functioning as a piston upon impact pushing the hollow point open. A copper-plated hollow-point loaded in a .44 Magnum, for example, with an original weight of 240 grains (15.55 g) and a diameter of 0.43&nbsp;inch (11&nbsp;mm) might mushroom on impact to form a rough circle with a diameter of 0.70&nbsp;inches (18&nbsp;mm) and a final weight of 239 grains (15.48 g). This is excellent performance; almost the entire weight is retained, and the frontal surface area increased by 63%. Penetration of the hollow-point would be less than half that of a similar nonexpanding bullet, and the resulting wound or permanent cavity would be much wider.

It might seem that if the whole purpose of a maximum disruption round is to expand to a larger diameter, it would make more sense to start out with the desired diameter rather than relying on the somewhat inconsistent results of expansion on impact. While there is merit to this (there is a strong following of the [[.45 ACP]], as compared to the [[.40 S&W]] and 0.355 in diameter [[9×19mm Parabellum|9×19mm]], for just this reason) there are also significant downsides. A larger-diameter bullet is going to have significantly more [[drag (physics)|drag]] than a smaller-diameter bullet of the same mass, which means long-range performance will be significantly degraded. A larger diameter bullet also means more space is required to store the ammunition, which means either bulkier guns or smaller magazine capacities. The common trade-off when comparing .45 ACP, .40 S&W, and 9×19mm pistols is a 7- to 14-round capacity in the .45 ACP versus a 10- to 16-round capacity in the .40 S&W versus a 13- to 19-round capacity in the 9×19mm. Although several .45-caliber pistols are available with high-capacity magazines ([[Para Ordnance]] being one of the first in the late 1980s) many people find the wide grip required uncomfortable and difficult to use. Especially where the military requirement of a nonexpanding round is concerned, there is fierce debate over whether it is better to have fewer, larger bullets for enhanced terminal effects, or more, smaller bullets for an increased number of potential target hits.