The VSKA rifle features an all new bolt carrier, front trunnion, and feed ramp machined from S7 tool steel and specially heat treated for maximum durability. S7, often referred to as a “Shock-Resisting Tool Steel,” is commonly used for tools like chisels and jackhammer tips as it has maximum shock resistance and high compression strength, while retaining toughness. The front trunnion and bolt are machined from billet and exceeded the durability goals for the project.