- "Straight-pull bolt-action custom built rifle, with integrated mutli-zoom scope. Chambered in .300 Win Mag."
— In-game description
The CSRX 300 is a slow-firing bolt action rifle that fires powerful penetrating rounds. The weapon does not have any attachments, but comes equipped with a variable 5x and 12x scope. The rounds fired by the weapon can penetrate up to 5 surfaces (breakable walls and operators), and will instantly down players by hitting them in the torso.
CSRX 300 bullet strikes can also stagger Shield operators like with melee attacks, allowing follow-up shots to damage the Operators behind the shields.
Shots from the rifle have a very strong destruction profile, able to create large holes on walls with single shots and are able to instantly destroy both hatches and wooden barricades. Unlike shotguns, the CSRX 300 cannot destroy wooden supports within destructible walls. Like the OTs-03, the CSRX 300 can shoot through the bulletproof windows on Plane.
Despite these benefits, the rifle also creates a notable sound and smoke trail which can be used to track the player's location. Operators put in a DBNO state by the rifle will also automatically face the direction they were shot from, allowing them to call out the location of the enemy player to their teammates. The rifle itself cannot penetrate reinforced objects, but this is offset by Kali's LV Explosive Lance.
Having the CSRX 300 actively equipped will incur a slight speed penalty. Equipping Kali's secondary will avoid this speed penalty.
- The base inspiration for the CSRX appears to be a Blaser R93, as indicated by the straight pull bolt and removeable magazine action. However, the chassis applied to the base system appears to be inspired from the Accuracy International Arctic Warfare series, with some serious modifications to accomodate the Lance and various other recoil reducing features.
- The CSRX is the only weapon in Rainbow Six Siege that is incapable of equipping any attatchments.