Nickel Boron BCG??

[Dirty J]

Not to mention its plating. It can wear, chip, peel, etc.

I personally prefer the good ol'fashioned black bolt carrier.

 

[safellows1967]

I upgraded my AR15 with one and then when I built my 300 BO I purchased one for it. Just do some research and pricing before buying. eBay had some good deals on BCGs.