Some say that the hard chrome plating wears the receiver faster, because its harder (higher Rockwell) against the aluminum receiver than a standard bolt. But I don't buy that because at the same time the chrome plating leads to a smoother surface which actually reduces friction, being more non-porous. So I think the wear factor thing is pretty much a wash, but I would lean toward less friction, smoother surface being a better thing, with proper lubrication.
BUT..... that only applies as long as the bolt, before it is chrome plated, was smooth to begin with. If a bolt gets chrome plated that has any defects or is not smooth enough to begin with you will have a very, very hard filing action going on inside your receiver because the defect or roughness will now be extremely hard against the softer aluminum. If going to a hard chromed bolt, I would inspect it very closely for any burrs or imperfections, before using, that might cause excessive wear. After the first 100 rounds or so I would inspect the receiver for any unusual wear. The hard chrome in my experience will help the bolt be more self cleaning over a prolonged firing session or sessions (600-1000 rounds) because the harder smoother surface of the bolt gives powder residue less of a hold to accumulate onto the bolt surface, in a prolonged firing session or sessions.The fact is that the bolt gets dirty in a AR, the more gunk that attaches itself to the bolt the more potential there is for a malfunction. But I think in normal use an AR cleaned regularly should show no difference in function in a chrome vs non-chromed AR. Like Raccol said it cleans up easier, most likely due to the hard chrome plating. That also says to me, smoother surface/less gunk attaching itself to the bolt, that is not a bad thing in an AR.
And it looks purdy!
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