Chrome lining on an AR-15 bolt offers several advantages. It increases durability and resistance to wear, extending the bolt's lifespan. The hard chrome surface also improves corrosion resistance and makes cleaning easier. However, chrome lining can slightly reduce accuracy due to minor dimensional changes.
Alternative coatings include nickel boron and nitride. Nickel boron provides excellent lubricity and corrosion resistance, making the bolt smoother to operate and easier to clean. Nitride treatment, also known as QPQ or Melonite, offers similar benefits to chrome lining but with less impact on dimensions, potentially preserving accuracy.
Each coating has its pros and cons. Chrome lining excels in durability, nickel boron in smoothness and ease of cleaning, while nitride offers a balance of properties. The choice depends on the shooter's priorities and intended use of the rifle.
