Bolt Knob
The rounded handle end the shooter grips to cycle the bolt, often oversized so it is easier to find and run quickly under stress without leaving the scope.
The bolt knob is the rounded grip at the end of the bolt handle, the point where the shooter’s hand actually drives the bolt through its cycle. Lifting and pulling the knob rotates the bolt body, disengages the locking-lugs from the receiver, and lets the action open to extract and feed.
Precision and tactical shooters often fit an oversized knob, sometimes threaded on as an upgrade, because the larger surface is easier to find and seize without breaking position. A good knob lets the shooter run the bolt-action quickly and consistently while keeping eyes on target through the scope.