A rifle only shoots as well as what's holding it. This is the gear that takes your hands out of the equation — bipods, tripods, front and rear rests, bags, and adapters for the bench, the blind, and the field.
Bipods come in sling stud and Picatinny mounts, fixed and swivel, in heights from prone-low to sitting and kneeling. Shooting tripods carry a rifle or a spotter and hold steady on uneven ground where a bipod won't sit. Rests and bags do the rest of the work at the bench when you're zeroing an optic or working up a load.
Everything here pairs with what's on the other side of the rifle. If you're mounting a thermal or night vision scope, a stable platform is the difference between a hit and a story about one.