Hi guys, I was just inspecting one of my AR's that has a BCM BCG and lo and behold, I think the bolt has cracks running from both corners of the ejector hole where the flat face meets the sides. The gun has been sitting for a good long while since it's last been shot, so I think what we're seeing here is carbon being pushed out of the crack by oil through capillary action, making it apprear pretty obviously. I took the best picture I could, then I cleaned the face residue with Qtips and I can still see further parts of the crack ever so faintly. I would need a microscope to see it better.
BCG has less than 2000 rounds through it of various factory ammo. It's been paired since new with a new LMT 10.5" barrel.
Here are two pictures to illustrate what I'm saying. First picture is the bolt as I pulled it out of the gun, second picture is after I cleaned the residue off.
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Has anybody here seen this before?
BCG has less than 2000 rounds through it of various factory ammo. It's been paired since new with a new LMT 10.5" barrel.
Here are two pictures to illustrate what I'm saying. First picture is the bolt as I pulled it out of the gun, second picture is after I cleaned the residue off.
Has anybody here seen this before?