Cam Pin Wear On Upper. POFUSA Roller Cam Pin vs HydraFire Roller Cam Pin YouTube The upper IS made from aluminum and the cam pin from alloy steel after all As others have pointed out the POF roller cam pin should mitigate this
Cam Pin/Upper receiver wear from www.m4carbine.net
These are smaller than your standard cam pin and have a beveled or rounded edge that doesn't make contact with the upper and are more reliable than Mil-Spec. It appears now that the aluminum bearing surface in the upper receiver is not smooth where the bolt carrier rides and wear is revealing casting imperfections
Cam Pin/Upper receiver wear
These are smaller than your standard cam pin and have a beveled or rounded edge that doesn't make contact with the upper and are more reliable than Mil-Spec. 2.) My FFL also said some piston Ar15s have wear on the receiver extensions too, and that it often stops at some point. For your case, the cam pin wear is some what normal, just make sure it doesn't get worse (it shouldn't be a deep crack or anything)
Upper Arm Alignment Cam Pins Dirt King. It appears now that the aluminum bearing surface in the upper receiver is not smooth where the bolt carrier rides and wear is revealing casting imperfections With glasses and a magnifier I could not tell if the receiver was cracking so I put a macro lens on my camera for a closer view
LMT cam pin wear on upper r/ar15. I'm getting very slight wear on my AR15/.223/5.56 upper 2.) My FFL also said some piston Ar15s have wear on the receiver extensions too, and that it often stops at some point.