Grain FMJ (Box)” is a description commonly used for ammunition to indicate the weight of the bullet projectile and the type of packaging.

• “Grain” refers to the weight of the bullet. It is a unit of measurement commonly used in ammunition to indicate the mass of the bullet. The specific grain weight can vary depending on the caliber and specific product variant.
• “FMJ” stands for Full Metal Jacket. It is a bullet design where the lead core is fully encased in a harder metal, typically copper. FMJ bullets are known for their reliable feeding, smooth function, and reduced barrel fouling. They are commonly used for target shooting, training, and plinking purposes.
• “(Box)” indicates that the ammunition is packaged in a box. This is the standard packaging for most commercially available ammunition. The box typically contains a certain number of rounds, usually specified on the box, such as 20 rounds, 50 rounds, or 100 rounds.

It’s important to note that without specifying the caliber or brand of the ammunition, it is difficult to provide more specific information. Each ammunition manufacturer may have their own product offerings with different grain weights and packaging options.

If you have a specific caliber or brand in mind, I can try to provide more detailed information about the grain weight and specific product offerings in that particular case.