Gunsmithing Melonite in Bore: Removal?

[Blackstone]

Long story short.
I had a stainless Rock Barrel in .22-250 (proven shooter).
The rifle went back to smith for coating (since he was too busy to do it at the time of the re-barrel) in Melonite.
Recieved it back with Melonite in the bore (as well as on the outside) which was now blackish and not shiny stainless.
Smith says "shoot it" , don't worry about it.
I did and it is all over the place.
Not even consistent.
I'm supposed to leave for p-doggin on the 5th.
Any proven ideas on how to get this out, short of sending it back to the smith?

 

[darrenk75b]

Re: Melonite in Bore: Removal?

It's not a finish, but a metal tratment which ends up turning the metal black. You won't be able to remove it, sorry.

 

[Adam B]

Re: Melonite in Bore: Removal?

there is melonite in the bore but no where else? The entire barrel should be melonited, they fully submerge the barrels when they melonite coat them. My experiences with meloniting have been very positive

 

[9H_Cracka]

Re: Melonite in Bore: Removal?

A friend got one back and it had pressure problems immediately. Call the the meloniter and the answer of "Oh you gotta polish the chamber before you shoot it" came back.

First 50 shots, over a chrono - the ES, SD, and on paper accuracy SUCKED out of a proven F-Open rifle and broken prior to treatment barrel.

It started to settle down at around 50 rounds post meloniting. I'll get an update tomorrow on it after another range trip with the chrono.

 

[Brutas]

Re: Melonite in Bore: Removal?

Find out from your smith who did the Meloniting and contact them directly.

How was the gun cleaned before going to meloniting?

Do NOT try to lap it out. Meloniting changes the surface hardness of the steel. To lap out the meloniting, you would be making it a smooth bore of a slightly larger caliber and wrecking your throat and crown.

 

[Blackstone]

Re: Melonite in Bore: Removal?

To be clear, I don't care how the bore "looks".
I only care about the fact that a proven accurate shooter is now spraying shots (same ammo/same scope etc.).
Is there an expedient I can try to remedy this?
I put about 20 rounds through it yesterday.
Will firing more rounds really help?
Or is this gun going back to the smith instead of with me p-doggin in the 5th?

 

[Chiller]

Re: Melonite in Bore: Removal?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: _9H</div><div class="ubbcode-body">A friend got one back and it had pressure problems immediately. Call the the meloniter and the answer of "Oh you gotta polish the chamber before you shoot it" came back.

First 50 shots, over a chrono - the ES, SD, and on paper accuracy SUCKED out of a proven F-Open rifle and broken prior to treatment barrel.

It started to settle down at around 50 rounds post meloniting. I'll get an update tomorrow on it after another range trip with the chrono. </div></div>

Leo would love to hear how this ends up. Really been on the fence on this process.

 

[hntbambi]

Re: Melonite in Bore: Removal?

I would not expect the rifle to have the same pet load post treatment. You are changing the surface of the barrel which could change the harmonics.

I'd shoot the gun some more, work up a new load and go frag some p'dogs.

 

[taseal]

Re: Melonite in Bore: Removal?

Who did the coating?

In my research, the only people that should touch a barrel to melonite it should be mmi-trutec.

I have a feeling that it was someone who doesn't specialize in gun barrels, and now yourr barrel is ruined.

It really makes the barrel hard, so I'm not sure shooting it more is gonna do anything

May e you can try to use smooth-kote and see if it'll add some lubrication to the rifling,

Besides that, you might be SOL

But yeah, who did the meloniting?

 

[frankythefly]

Re: Melonite in Bore: Removal?

A friend of mine ran into the same problem, he had to change his loads completely. After about 100 rds the barrel seemed worked in, and he had developed a new load. Can't say that it was shooting 100rds that"fixed" it or if it was developing a new load or a combination of both. Either way your old loads will shoot slower (80-100fps)with Melonite treatment and most likely wont be accurate. Disregard any previous load data and start over.

 

[taseal]

Re: Melonite in Bore: Removal?

Umm, not sure about slower,

I talked to Joel Kendrick (goto for melonite barrel stuff) and he said you will get about 1% higher with melonite. At 2700 fps, you're looking at 20-30 increase.

Honestly, if you are getting your barrel do e by anyone but mmi, you risk messing up the barrel. And you're gonna get some negative results.

Rock creek and rws uses mmi.

 

[frankythefly]

Re: Melonite in Bore: Removal?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: taseal</div><div class="ubbcode-body">Umm, not sure about slower,

I talked to Joel Kendrick (goto for melonite barrel stuff) and he said you will get about 1% higher with melonite. At 2700 fps, you're looking at 20-30 increase.

Honestly, if you are getting your barrel do e by anyone but mmi, you risk messing up the barrel. And you're gonna get some negative results.

Rock creek and rws uses mmi. </div></div>

Anytime you reduce friction in a barrel you reduce pressure, in turn reducing velocity. Sounds like he doesn't know what he is talking about.

 

[taseal]

Re: Melonite in Bore: Removal?

Yes, you decrease pressure, so now you add more charge, and there you go.

With lessened friction, you should get slightly higher speeds.

 

[MinorDamage]

Re: Melonite in Bore: Removal?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: taseal</div><div class="ubbcode-body">Yes, you decrease pressure, so now you add more charge, and there you go.

With lessened friction, you should get slightly higher speeds.

</div></div>

We are talking about keeping the same load pre and post melonite. When you decrease pressure with an equivalent charge your velocity will decrease. It is the same principle as moly or HbN. It doesn't necessarily mean you can get more velocity. You may be able to bump the charge (same pressure) and get the same velocity with less friction. Less friction equals less wear.

Josh

 

[John L]

Re: Melonite in Bore: Removal?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Blackstone</div><div class="ubbcode-body">
I had a stainless Rock Barrel in .22-250 (proven shooter).


Recieved it back with Melonite in the bore (as well as on the outside) </div></div>

How much was the barrel shot before treatment? Should be less than 50 rds.

Something don't sound right here. Are you talking about Melonite treatment or some other type of coating? Reason I ask is your original post just sounds strange. It does not make sense.

 

[taseal]

Re: Melonite in Bore: Removal?

Isn't the pressure going to be higher because the metal is harder though. Less expansion of barrel, causing higher pressure.

It's like blowing into a balloon vs a metal pipe,

Just an educational guess.

 

[longrange4me]

Re: Melonite in Bore: Removal?

I sent 5 barrels in to be melonited by MMI Trutec, 2 new, 3 used. I had mixed results. New barrels 1 shot well 1 shot poorly. Used barrels, known good shooters 2 shot poorly 1 shot well. It was a small sample but seemed like a crap shoot to me. In my experience I would not melonite any more barrels. The barrels that shot well did last much longer than expected, including a 6.5 x 284 that got 1600 rounds before the groups opened up. I usually expect 800 to 900 rounds out of a 6.5 x 284.

John

 

[Blackstone]

Re: Melonite in Bore: Removal?

Update:
I re-cleaned the bore with Sweets followed by a rigorous 100 strokes or more with about 20 patches prepped with J-B Non-Embedding Bore Cleaning Compound and Shooter's Choice.
The blackness still kept showing up on the patches.
I also vigorously brushed the chamber.
I fired an additional 20 or so rounds and the groups began to tighten up <span style="font-weight: bold">almost</span> to the point the barrel was at before it was Melonited. It is sub-MOA, but not remakable.
I'm taking it prairie dogging in two days, (along with other reliable rifles), and it should have a good work out and I will report back then.

 

[former naval person]

Re: Melonite in Bore: Removal?

If you use J-B compound on any barrel you will get black patches until you quit using it. JMHO

 

[Goin'Hot]

Re: Melonite in Bore: Removal?

I have about 500 rounds down my barrel after treatment and my last "clean" patch is still a little gray. MMI did my barrel for me.

It cleans up really quick but, I never get what I would call a truly "clean" patch. It is a WHOLE LOT cleaner than my initial cleaning after the process.

 

[sandwarrior]

Re: Melonite in Bore: Removal?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Blackstone</div><div class="ubbcode-body">Update:
I re-cleaned the bore with Sweets followed by a rigorous 100 strokes or more with about 20 patches prepped with J-B Non-Embedding Bore Cleaning Compound and Shooter's Choice.
The blackness still kept showing up on the patches.
I also vigorously brushed the chamber.
I fired an additional 20 or so rounds and the groups began to tighten up <span style="font-weight: bold">almost</span> to the point the barrel was at before it was Melonited. It is sub-MOA, but not remakable.
I'm taking it prairie dogging in two days, (along with other reliable rifles), and it should have a good work out and I will report back then.</div></div>

Hopefully we can get another update when you get back. I'd be interested to see how this melonite holds up. FWIW, when I logged, the chainsaw bar ends were made of either melonited steel or stellite. Since the wear was the worst around the tip and the drive sprockets they had to be made really hard. I would typically have to file the bar down weekly to get rid of the sharp wire edges created by the chain wearing it. The tips didn't do that. Besides, you couldn't get a file to even take a bite on it.

Also, I'm in agreement that meloniting the inner surface of the barrel changes that barrel and it's not going to hit like it did. You will need to work up a different load. BTW, did the general POI change from your original load? Even though the groups got bigger, did they shift, L-R or U-D?
And if you reduce friction that will make the bullet go faster. Even though it would seem like it, the international gas pressure law doesn't apply so much here. The powder burns from between 19,000-24,000 fps depending on what was loaded. The hottest bullets come out the barrel @ 4000 fps. And, depending on how fast your powder is, you can achieve highest pressure in 2" down the barrel all the way to 15" down the barrel. In one case, reduced friction helps velocity. In the other case where maintained pressure is supposed to be driving velocity, it hurts velocity. But, again, you have that gas expanding at much faster than the bullet is traveling that retains most of the velocity.

Anyhow, if it's not too late to warn you to let that .22-250 cool a bit or you'll burn it out in one trip.

Then whether you melonited it or not...it won't matter.

 

[Fred_C_Dobbs]

Re: Melonite in Bore: Removal?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: frankythefly</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: taseal</div><div class="ubbcode-body">Umm, not sure about slower,

I talked to Joel Kendrick (goto for melonite barrel stuff) and he said you will get about 1% higher with melonite. At 2700 fps, you're looking at 20-30 increase.

Honestly, if you are getting your barrel do e by anyone but mmi, you risk messing up the barrel. And you're gonna get some negative results.

Rock creek and rws uses mmi. </div></div>

Anytime you reduce friction in a barrel you reduce pressure, in turn reducing velocity. Sounds like he doesn't know what he is talking about. </div></div>
Telling Joel Kendrick he doesn't know about salt bath nitriding is like telling R.J. Oppenheimer he doesn't know about atom bombs.

I coat varmint bullets with either WS2 or hBN, so I'm familiar with the fact of "slicker is slower." That does tend to be the case if all you're doing is making the bore slicker, but SBN also increases its indentation hardness. In fact, on the Rockwell C scale, it about doubles it. Increasing indentation hardness improves gas checking and reduces blow-by, which increases MV enough to offset the loss from the additional slickness.

The only barrels I have (at the moment) that were SBN treated are Glocks but I do have several acquaintances who've had varmint rifle barrels treated by MMI. They all report a slight bump in MV.

Israel Military Industries and Accuracy International both advertise they're "nitriding" their barrels but I believe they're referring to SBN.

 

[scotharr]

Re: Melonite in Bore: Removal?

I had 7 barrels nitrided. They are were all new and I didn't bother with any break in before getting them treated. They all shoot great...like 590's in F-Class. I've been told their is a learning curve with meloniting barrels and MMI Trutec knows what they are doing. Call Joel Kendrick if you want to talk to someone with lots of experience. He represents MMI-Trutec for shooters.

The treatment makes the barrel harder/smoother, thereby reducing velocity/pressure with the same charge. This is a similar effect to moly coating bullets. In both cases, you ultimately get higher velocities than before treatment after you up the charge. In short, you end up with higher velocity with the same chamber pressures....but that requires different charge weights before and after treatment.