Can anyone give me tips on drilling holes in carbon fiber?  (I know I need to wear a respirator to avoid breathing tiny pieces of it.)  

I'm planning some upgrades to my ultralight build.  I plan to replace the Cav Arms Mk. II lower with a Bushy Carbon 15 lower and telestock (same weight per Forest's weight chart), shave the FSB and lose the rear sight.  (I always use the OKO 4W anyways.)  While I'm at it, I thought I might drill holes in my one-piece carbon fiber handguard/free-float tube to shave off a little more weight and give it that cool "perforated barrel jacket" look.

use a really high speed drill to keep the carbon from splintering and if possible start with a small bit and work your way up.


i found out the hard way


see my avatar? about 40% of the car is carbon fiber and it had to be fitted.

I used to inspect Carbon fiber tubes for a commercial composite company (These were not AR related tubes)

This was 10 years ago and drilling them was hard to do . I'll tell you how an engineer finally figured out how to do it .

We had drill bits made that actually ground as well as cut , and it was slow RPM speed (relative) . They didnt last too long but they were clean and acurate .

That was then , this is now . There could be much better ways now but we found abrading rather than cutting did the trick . Good Luck