Hi Steven and welcome. The string GC9+P+CM10 is the exact manufacturer part number (MPN) for a specific load manufactured by Grizzly Ammunition. Here is what the individual components of that specific ammunition mean: GC9: Stands for Grizzly Cartridge 9mm (the manufacturer's line identifier).+P / +P+: Stands for Overpressure ammunition. These rounds are loaded with more gunpowder than standard 9mm ammunition, generating higher muzzle velocity, energy, and chamber pressure (which translates to more recoil and muzzle blast. Cheers, stay safe and enjoy!

GC9+P+CM10 is the specific product code for Grizzly Ammo's 9mm +P 124gr Jacketed Hollow Point ammunition. This code helps identify this particular type of ammunition in their product line.

In the context of 9mm ammunition, GC9+P+CM10 is the manufacturer's specific product code for Grizzly Ammo rather than an industry acronym.The specific letters and numbers in this part number break down as follows:GC: Stands for Grizzly Cartridge (the manufacturer).9: Caliber is 9mm.+P: Stands for "Plus P" or overpressure ammunition. This means the ammo is loaded with more gunpowder to create higher pressure and velocity than standard 9mm rounds.CM10: This is an internal code used by Grizzly to specify the exact bullet type—in this case, a 124-grain Jacketed Hollow Point (JHP).