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High round-count MR556/762 reports?

4462 Views 11 Replies 6 Participants Last post by  lifesizepotato
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.
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I haven't seen a single post or thread referencing the 10k round keyholing topic. I am not interested in the barrel lining, I am specifically asking about refuting the 10k-round sewer pipe and even, more importantly, regular guy owner reports at that sort of round count. I will search again, since apparently such threads are littering HKPro.

Edit: Still not finding anything searching for "mr556a1 henderson" and "mr556a1 keyholing," and virtually nothing at all on the topic posted since that Arfcom thread went up last summer. You'd think I'd be tripping over these daily threads, right?
Alright, towards the end of this one single thread I found, there are some people talking about the Henderson thing.

Would anyone with a high number of rounds through their MR like to weigh in with their personal experience? What should I search for to find all of those threads?
From the couple of guys in that one thread and augee's helpful response, it sounds like the explanation for Henderson's results is that constant full auto on an unlined barrel + unverified barrel cleaning + maybe the tapering are probably the main culprits.

I'd love to hear from regular HKPro owners with their high round-count MRs to see how they've fared, if they don't mind posting their stories for the umpteenth time.
Thank you. That second one is exactly the sort of discussion I was looking for. I probably missed it because I've been searching MR556A1.
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