that is refering to the weight of the bullet, for whitetail deer i like to stay 100gr. or higher mostley i shoot 125, 139/140

go to a shop and have them explain the make-up of the bullets, they all have a specific design for there intended use, some are made for target only, some are designed to do minimal damage, some a lot ofdamage, for deer hunting, a lot of people love ballistic tips, i have had my best luck with partitions, there are so many different types that it would be impossible for me to list all the types, go to some bullet manu. web pages they'll break it down pretty good. best of luck, is this to hunt? if so what kinda critters