Melonite

[C4IGrant]

There are a few manufacturers that I consider "top tier". They are probably the same ones the people on this site would put into that category.

My question is are their any top tier companies that make barrels with Melonite? As far as I know S&W does not sell barrels. I think I want to try one out.

DD would be one of the main ones.


C4

[ColtSeavers]

Regarding melonited 4150CMV barrels' longevity, AR Performance states that:

Melonite treated barrels have proven to last 30% longer than chromelined barrels and*are more accurate.

Melonite treated barrels have proven to near twice as long as stainless barrels and*are just as* accurate.

The 4150 11595E steel Melonite(QPQ) treated barrels we sell will last twice as long as stainless barrels-*of the stainless. The *final finish meets or exceeds stainless steel corrosion resistance.* 416 stainless barrels .980" in diameter do not meet the 2:1 burst/hoop strength safety ratio required by the firearms industry standards in anything larger than the 5.56. We only use the stronger 4150 11595 E barrel steel in all of our barrels.

I'm sure some quick googling would also show more longevity testing and corrosion resistance results as well.

[Col_Crocs]

No hands on experience but BA has been getting good reviews too, atleast from what i've seen. I've been very interested in melonite since reading that long thread both for the extreme corrosion resistance and the reported durability over chrome. Here's an interesting post by Phreakish in response to my asking if BCM had any plans for melonite barrels:

Can't comment on plans for the future.

As far as nitride, it's not easy to accomplish and in most cases the result is as good as, maybe even slightly better than, a typical forged and chrome lined barrel. The greatest benefit of nitride is the ability to protect and coat every part of the barrel, including the gas port. However, nitride treatment of an assembly is usually not done due to the molten salts getting between parts and continually weeping out over time. If the assembly isn't coated, then the gas port is likely going to be drilled after the nitride treated barrel is mated to an extension, in which case we lose a huge benefit of nitride and we're back to a part that's equivalent to a chrome lined barrel. That's not insignificant though, since chrome plating processes are finding their way ever closer to the center of the EPA's crosshairs and we'll need something to replace chrome when the day comes.

Nitride treatment is also significantly different than the types of treatments the typical materials are given, so it would take some real engineering to ensure that the processes and materials are compatible to truly improve upon the hammer forged and chrome lined barrel, rather than degrade or simply meet the same performance threshold.

TL;DR: There's a lot more to it than just tossing a barrel cluster in a salt tank. There's definitely benefits to be had, but it needs to be done right and even then the result is likely to be equivalent to and not hugely better than a chrome lined barrel, at least while chrome is still viable.

[constructor]

Lietner Wise before it changed to LWRC was one of the first to use Melonite on a rifle barrel. Also one of the first to use 9310 to make bolts. I found several reports online around 2005 where he had submitted test results to the military. The results were impressive when 4150 CMV 11595e steel was used.
I would like to see it first hand or videos of mag dump after mag dump until the barrel burst and another test of normal fire rates but for endurance rather than heating them until they fail.
Stainless barrels do not meet the 2:1 safety factor for strength needed around the chamber in a 5.56 let alone larger cartridges. Many use a maximum yield strength of 416 to calculate it but the barrels as used are only 28-32 rockwell and do not come close to the published max yield numbers. The mil specs 4150 11595e for a reason.
In the end you will spend $40,000 in ammo to wear out a $200 barrel.

[Junkie]

I have a Ballistic Advantage barrel, they say it's 4150CMV and it's nitrided. It's 5.45x39 and I've shot 7N6 out of it and then not cleaned it for a couple days with no signs of rust, but I haven't done the same test in a chromed barrel so I can't really compare it to anything else.

[Hmac]

So...I guess no experience to report on throat erosion, gas port erosion, or other longevity issues on the Sionics melonite barrels.

I have 10,000+ on my Noveske 16 inch mid length with no noticeable loss of performance, and close to that on my BCM 11.5. I'm pretty comfortable with chrome lining performance, but I'd sure go melonite in general and Sionics in particular if it offers even close to similar performance.

[Mjolnir]

What's the common perception of Aero Precision barrels?


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"One cannot awaken a man who pretends to be asleep."

[BrigandTwoFour]

What's the common perception of Aero Precision barrels?

I think they're too new to the market for any real solid opinions to be out there. I've been working on a 308 project, and have been stuck between a Fulton 18.5" chrome lined (known quality), or one of Mega's melonited 308 barrels. There just doesn't seem to be much information about anyone's melonite barrels out there.

[ramairthree]

I have two builds with the Melonite / Black Nitride barrels, a cheap cromoly build, chrome lined builds, and a stainless.

The last M4 I had (8 years), had two barrels replacements for throat erosion, and I believe a total of three bolt lugs off two different bolts.

But I did not think I had a particularly high round count. Definitely not 40K between barrel changes. And did not kill the EoTech 552 or A.R.M.S. rear sight. PEQ got updated about 6 years in, but never got in the same abuse and round count the last two years as the first 6.

All green tip.

I suspect many factors can change barrel wear for a given round count and some materials offer advantages others don't in those. If I went through 4K rounds in two days while constantly being poured and a wipe down or two vs. I went through 8K rounds in a year at 1K a day spread out and thoroughly cleaned in between may result in same amount of wear.

Long term experienced armorers I would love to hear your opinions on the standard Colt M4 barrel wear regarding this,
but I am not sure if people have wracked up the same pool of experience in sheer numbers and round counts with other materials.

[Col_Crocs]

Constructor: Do you have a copy of that report to post? I'm interested to see what it has to say about the things Hmac touched on like throat erosion and gas port erosion.
I tried a quick search on google but only dug up a thread on weaponeer on Hatcher's Notebook. I went straight down to where Tennifer and Melonite were discussed and reading it got me curious... The guys says the surface needs to be precisely machined and thoroughly polished prior to treatment and says that in the past, barrels had to be lapped 3 additional times. I assume this is due to the extreme hardness of the resulting surface and length of time you would need to break it in if it weren't prepped like so. Is this still the case or has the process significantly shortened with today's technology? Secondly, how many steps does it add to the manufacturing process compared to chromed and parked barrels? I assume there are already additional steps like assembling, disassembling, tracking, treating and reassembling just to treat the barrel post-porting?