Atomic's 9mm +P ammunition is designed to hit hard, penetrate deep and shed petals during expansion. The loss of petals allows for additional wound paths increasing the likelihood of striking a nearby blood vessel, organ or central nervous system all while reducing the core weight to protect against the danger of over-penetration. The central core should expand to 150% of the original diameter, retain 75% or more of the projectile's weight and penetrate not less than 12 inches of ballistic medium. Due to the unusual shortage of ammunition components and difficulty in obtaining new, PLUS P (+P) marked cartridge cases, some +P(+P) ammunition may be loaded in NEW standard cases. At Atomic Ammunition they know that you carry and use real guns, not test barrels. All of their external ballistic information is obtained from tests using common firearms that you are likely to own and use, not inflated, misleading information from test barrels. They feel that this is the most accurate and useful information for customers, so it is the only information that they provide.