Tikka M558 and M658 Bolt Shroud

This bolt shroud is a faithful reproduction of the now discontinued factory spare part made from 1989 to 1990 (Tikka reference: S5840244). We machine these from 4140 chrome moly steel then they are QPQ nitrided to a high surface hardness which produces a black color closely matching the blued finish on these rifles. Bolt shrouds are designed to protect the shooter's face in the rare event of a cartridge rupture or failure, where hot gas and powder debris can travel back through the bolt body via the firing pin hole. Externally our design is very similar to the factory original with a few small changes to accommodate the CNC machining required for manufacturing.

Note

• We include a small coil spring which is identical to the design that Tikka supplies on the newer T3x models with their steel shrouds. This coil spring takes up the slack of a necessary tolerance designed into the shroud to ensure proper function of your firing pin. Installing the spring will maintain your shroud's alignment to the bolt and also remedy any minor metal-on-metal noise when out hunting, something which is not a consideration with the original factory plastic shroud.
  

Construction

• Shroud: CNC machined from 4140 cro-moly steel, QPQ nitrided (black color)
• Coil spring: wound from stainless steel wire
  
• Weight: 0.88 oz (24.6 g)