I had a customer who wanted me to build him a 6.5 grendel with a proof research barrel, so he provided the barrel and bolt. He wanted the Clark Custom carbon fiber handguard and a billet slick side upper. We put a nickel boron bolt carrier in with his bolt and shot it today, I was quite impressed with the way it shot and the weight savings. This upper complete with bolt carrier was 3.4lbs.
The guys are Proof Research have a very nice product, but from what I saw on their site, it doesn't come without a price. Great build for a great guy!

The guys are Proof Research have a very nice product, but from what I saw on their site, it doesn't come without a price. Great build for a great guy!
