The HSM 300RUM12N Game King 300 Remington Ultra Magnum 165 gr Sierra GameKing Spitzer Boat Tail rounds deliver the kind of long-range accuracy and terminal performance hunters ask for when chasing elk, moose, or long-distance big-game shots, and the Sierra GameKing Spitzer Boat Tail series is known for a high ballistic coefficient that flattens trajectory and reduces wind drift for cleaner, more confident shot placement. The 165-grain bullet weight balances sectional density and velocity for deep penetration on heavy game while the brass casing promotes consistent chambering and reliable cycling in bolt-action and magnum platforms; shooters will appreciate the predictable point of impact and repeatable group sizes when dialing in optics or making extended shots. If you hunt mountainous terrain, glass for targets at distance, or need a load that carries energy to range under variable conditions, HSM 300 RUM ammunition gives the consistency and external ballistics to stretch effective engagement ranges, and search-friendly terms like 300 RUM ammo, Sierra GameKing 300 RUM, and 165 gr 300 RUM help when comparing ballistic charts and load performance.