M249 Barrel Steel?

AR/M4 AR Technical Discussion
1

My buddy sent me a link to a $1,900 subwoofer and said, “I want this.” I recently started educating him on the in’s and out’s of the AR-15 (mostly with links to m4c threads) so he’s also been talking about wanting to get one. So I dutifully pulled up a $1900 Noveske, sent him the link and asked, “Do you still want to get that subwoofer?”

Anyways, looking at the specs, he realized that he now knows enough to actually understand and make sense of what he’s looking at. But he asked me “Okay, what exactly is M249 barrel steel?” From what I’ve found (http://www.defensereview.com/noveske-rifleworks-n4-light-recce-carbine-john-noveske-interview-part-one/), it seems that the most accurate answer is:
“The steel defined by the TDP for the M249.”

Not especially satisfying.

So is anyone able to enlighten me? Is it different than 4140 or 4150? Is there something out there that describes it and its differences? Or do only people with the TDP know?

2

I dont know specifics, but if you reason with the fact that it is for a SAW and not an M4, you can conclude that the SAW should have a higher standard.

3

Only those who have signed an NDA have access to the TDP, but the steel is 4150 or better. Reportedly, the substantially greater longevity of the barrel is in large part due to the chrome lining, which is twice as thick as that supplied in the M4/M16.

4

It is specifically chosen over ORD4150 and CMV for use in belt fed machineguns.

5

Well, that’s certainly true, but the double-thick chrome lining is mentioned separately, so my supposition is that the material used for the barrel is somehow different as well.

So, it could be reasonably assumed that it is a different type steel which is, in certain aspects, superior (at least for weapons like the SAW) to what might otherwise be used in an AR-15 carbine or rifle? [As opposed to the same type of steel but selected from batches which have fewer impurities or whatever–sort of like how they build sniper-grade or accurized weapons by selected especially accurate (but otherwise stock) components?]

6

It is a different alloy than ORD4150 or CMV, and conforms to 3.4.1 of MIL-B-11595E for quality and cleanliness of the steel.

7

Cool. Thanks.

Also, keep making terrific weapons. I love mine and I’ll try to convince my buddy to put his money into one of his own instead of an overpriced sub.

8

Thanks for the info, Todd. I have a Light Recce Basic w/VIS on order, should be arriving here in Minnesota in the next week or two (fingers crossed). I’m anxious to get it on the bench, then I have a course with Sully end of July, a local course in September, and TriCon in October. In the process of stocking ammo now. Those three plus training ought to be good for about 5,000 rounds in the next few months.