This has been bugging me since I became 'AR Aware': There's a milled cut on the left side of every upper I've looked at, and an associated lump, hump or boss on the outside. (See pic) For the life of me, I can't see any purpose to it, but I know machinists aren't paid to make pointless cuts on manufacturers' products.
If some kind soul would shed a little light on this, I'll sleep much better. Thank you
Posted: 5/17/2008 3:26:40 PM EDT
[#1]
Posted: 5/17/2008 3:27:19 PM EDT
[#2]
its so your bolt cam can rotate, an AR simply would not work with out it.
Posted: 5/17/2008 3:32:34 PM EDT
[#3]
It's to allow rotation for the cam pin on your bolt as it slides in & out of battery. Take a look at your bcg & you'll figger it out.
Edit: got beat again.
Posted: 5/17/2008 3:44:14 PM EDT
[#4]
Oh. I see it now; I guess I didn't realize how far that cam rotated. Thank you all; I will sleep soundly tonight. Rob