For those who have a lot of rounds through their MR556/762s, how have they been holding up for you, and how many rounds have you put through them?
I'm especially curious about that infamous chromeless barrel, as there's a popular thread on another forum where a guy who runs a high-volume range in Las Vegas said their MR556A1 was keyholing badly by just 10,000 rounds. Since being posted lasted summer I've seen this referenced around the internet as proof that HK's ARs are overpriced garbage, so I'm wondering if other people have been having that issue or if it's a matter of running solvents through the barrel or what. I only have a few thousand rounds through mine but haven't had issues yet, though I admit I don't run it as "hard" as others. I have no desire to stir up the chrome lining debate for the millionth time, it is what it is, but is having the barrel shot out by 10k rounds (as his report implies) to be expected?
And I'll probably never come close to 10k on my 762 but I'd be interested to hear about those as well.
Apologies if this has been discussed somewhere, Googling and HKPro search didn't turn up anything except that Arfcom thread.