Now that Bushmaster is offering the Carbon Fiber Upper Receiver and Lower Receiver for sale, I am thinking about building an ultralight rifle with a 16" Light Weight Bushmaster Barrel.  

Will all AR-15 parts work with the carbon fiber receivers such as the normal bolt and carriers, KNS anti-rotational pins, RRA 2-stage trigger?  Will the parts just drop in?

Are there any issues with Carbon Fiber Rifles?  

Can carbon fiber parts be spray painted with krylon?

This would be my third build

good question, the bolt and carriers i'm sure will work but I dont think the rest will

I beleive the lower receiver uses regular lower parts.  The barrel to upper connection is special, Bushmaster wiull do that for you.  Not sure about the B/C/CH stuff.

Heck, call Bushmaster, they will know

My son just did a build with a Bushmaster carbon upper and he used a regular bolt, bolt carrier and charging handle.  I am glad to hear that Bushmaster is offering the lowers seperate because he wants a complete carbon rifle.

I called Bushmaster several weeks ago and asked about them (before the catalog... and they quoted me a cheaper price too! )

Anyway, the tech said that the newest carbon "M4" type uppers and lowers were 100% compatible with plain ole AR15 barrels, stocks, and other parts just like any other upper or lower.

it is just a shame to have $400 in an upper and a lower rather than $200 for both.  That money could go towards optics.  

Then again, you will have a rifle that you could fire one handed leaving your other hand free to negotiate the anchor chain of the ship that you are attacking, hahaha.

I wonder about the carbon fiber barrels that I saw on here a few months back.  They were pricey, but it would be interesting to see if they to, would work with these parts.