current source/ data on salt bath nitrating / melonote
- Thread starter CMaier
- Start date
NezRongero
Member
All my competition rifles, except for one, have Melonited barrels. All the barrels are SS and I hate shiny barrels especially when laying down on the ground with bright TX sun bouncing off the shiny SS barrels. I am not going to state any barrel longevity to save others from wasting their valuable time challenging the claim and asking for scientific, controlled experiment for proof, but I do like the black finish of the Melonited SS. I did test a couple of barrels and established their grouping capability, testing them after the treatment did not show any degradation in precision.
I used to send my weapons to a gunsmith in Ohio for the treatment, then found out Houston Unlimited in Chappell Hill, TX, does Meloniting, but they are not in the firearms business. They do a lot of work for the oil industry. They took in the first batch of barrels from our group in Austin a couple of years ago, and we sent them 2 more batches since. Their batch is like $170 and that will cover 3 barrels, there is an incremental minimal charge for additional barrels. Their work is at par with the operation in Ohio, not surprise since they both have the same equipment and the same process
Besides the barrels I sent my turning, and tapered expanding mandrels. They are almost like carbide in performance. I think they charged additional fee that amounted to about 2 bucks each item.
One thing, both places I use for the treatment do not do good enough job in washing and cleaning the bore and the chamber. On the other I don't think I want them scrubbing the bore, though the finish is quite durable. The residue comes out like brown mud color. JB takes the residue very well.
Nez is a smart fella, and I do not doubt what he says one bit. Nez has been helping me out a bit on an AR project and I appreciate that very much.
With that said, at the last benchrest match I attended, I loaded next to an employee from Bartlein. We discussed all sorts of things over the weekend and melonite was one of them. Long story short, and I truly don't remember why, but Bartlein doesn't recommend the process on their barrels. According to this employee anyway. I wish I could remember what all he did say, but I don't recall!!
I know Butch has had some barrels done, and if I remember correctly he has always had good luck with them.
If color is all your after, maybe cerakote is the answer?? lee
With that said, at the last benchrest match I attended, I loaded next to an employee from Bartlein. We discussed all sorts of things over the weekend and melonite was one of them. Long story short, and I truly don't remember why, but Bartlein doesn't recommend the process on their barrels. According to this employee anyway. I wish I could remember what all he did say, but I don't recall!!
I know Butch has had some barrels done, and if I remember correctly he has always had good luck with them.
If color is all your after, maybe cerakote is the answer?? lee
NezRongero
Member
Just enough to establish zeros and precision, maybe around 50 rounds.
NezRongero
Member
My dedicated LR M1A has a Melonited 11 T Krieger with over 6K rounds launching mostly 168 Hybrids at 2800 or 185 Jugs at 2650. Those are some hot loads for a 22 inch barrel. BTW, no dropped primers or flattened primers. The last time I took it out a local match, the Melonited barrel hit the 18x24 gong at 1K yards 6/10 with irons.
Butch Lambert
Active member
I have posted this email before.
This is from a military armorer
I was the Armorer for the Army Reserve Shooting Team for over a decade so I do have quite a bit of experience with both processes.
As I am sure you know, most G.I. barrels are made from chrome molly steel which is more susceptible to corrosion than stainless steel. Chrome lining is used on G.I. bores both to extend their shooting life and to protect them from corrosion that can be a problem in battlefield conditions where maintenance is sometimes sporadic or insufficient. Chrome lining does a pretty good job of protecting battlefield weapons. One of the objections to chrome lining is that it is thought to decrease accuracy. This seems to be a valid criticism and is backed up by machine rest tests I have conducted of identical barrels (same manufacturer but half chrome lined and half not).
As you are aware most barrel "wear" is in the throat area. So eventually the hot gasses from the burning of the gunpowder will eat thru the chrome lining at the throat. It is rumored that at this point accuracy will plummet but I have not found that to be true. (Or if true, it is overstated or maybe only occurs for that short period when there is both chrome and bare steel in the throat simultaneously - just at the point of initial break thru.) Chrome lined barrels can continue to shoot well for thousands of rounds after the bare barrel steel at the back of the barrel (throat) has been exposed due to erosion of the chrome lining. Another criticism of chrome lining is that it can flake off later in the life of the barrel resulting in poor accuracy. Obviously, this could also cause maintenance problems if the user is depending on the chrome to ward off corrosion and thus is careless in his bore cleaning. If corrosion is allowed to occur pitting will result and that will ruin accuracy for sure.
Barrel pitting was one of the reasons I got involved in Salt Bath Nitriding. I was loosing nearly as many expensive match grade barrels to improper maintenance (causing pitting) as I was to wear out. This was under the relatively benign target shooting conditions. Obviously given the reputation of degraded accuracy, using chrome lining wasn't an option. So for the past couple of years I have been Salt Bath Nitriding all of my match barrels and haven't had a single one exhibit any pitting. During that 2 yr. period shooters have put anywhere from a few hundred rounds to thousands of rounds on said barrels. I don't know how long the coating will persist so at this point I am still evaluating it as a preservative. I don't know what will happen in another year or two when these barrels get more wear on them. Salt Bath Nitriding goes on both inside of the bore and on the outside surface. So, instead of 2 manufacturing steps you have combined them into one. Salt Bath Nitriding doesn't degrade accuracy one iota, unlike chrome lining. This was the first thing that I verified when I began using the process. I broke in a bunch of barrels and then machine rest tested them for group. I recorded and kept the targets, cleaned up the barrels, and sent them to MMi TruTec for the Isonite process. When they came back I reassembled them on the same receivers with the same torque settings, same bolt carrier assemblies, same flash suppressors, etc. Then they were retested with the same ammo lots. NO degradation in accuracy and about a 1% increase in muzzle velocity.
Chrome lined barrels seem to clean up rather easily after a range session. I found the ease of cleaning of Isonite coated barrels to be similar to chrome lined barrels. The Isonite barrels clean up the easiest of any non chrome lined barrels I have ever used. Isonite can be applied to either stainless or chrome molly but the factory needs to know what steel you are sending them because the application process varies a bit. Again, I only have about 2 yr. of cleaning experience with Salt Bath Nitrided barrels. I don't know if the ease of cleaning will continue as the barrels get more rounds on them. Generally speaking, most non coated barrels get harder to clean later in life. Although stainless has a reputation of being corrosion resistant it isn't corrosion proof (I have had plenty of them return pitted) so I coat both my C.M. and my SS barrels. The Isonite on the outside of the stainless barrels cuts reflection down so my shooters like it.
I mentioned flaking of chrome lining inside the bore. Joel Kendrick is my contact at MMi TruTec, the company in Arkansas that does my Salt Bath Nitriding (they call it Isonite). He was mentioning using the Salt Bath Nitriding inside the bore prior to chrome lining it to get a better adhesion. He is currently working with one of the military contractors (maybe F.N., but don't quote me on that) relative to this process. He has given me permission to give out his contact information so I have cc'd him in my reply to you. He can give you the specifics of any testing and evaluation that has been done relative to this process and can give you quotes, etc. should you just be interested in the Isonite by itself as I use it.
One last quick note on chrome lining. Such barrels have the reputation of changing point of impact when heated up. I have found this to be very true. It may be due to the way the different metals (chrome molly and chrome) expand inside the bore. What ever the reason, it does happen and, again, this was verified on a state of the art machine rest. Isonite doesn't exhibit this characteristic.
I am sure you are well aware of some of the things I covered. Lacking specific questions, I just sort of used a shotgun approach which ended up being fairly long. If I left anything unanswered please feel free to get back to me. I have enabled my Spam Blocker to allow your e-mails to come in with out the automated hate responses that Earth Link sends out. I am sure Joel would also be glad to clarify the technical aspects of the Salt Bath Nitriding process. So far I am very pleased with it.
Best of luck!
This is from a military armorer
I was the Armorer for the Army Reserve Shooting Team for over a decade so I do have quite a bit of experience with both processes.
As I am sure you know, most G.I. barrels are made from chrome molly steel which is more susceptible to corrosion than stainless steel. Chrome lining is used on G.I. bores both to extend their shooting life and to protect them from corrosion that can be a problem in battlefield conditions where maintenance is sometimes sporadic or insufficient. Chrome lining does a pretty good job of protecting battlefield weapons. One of the objections to chrome lining is that it is thought to decrease accuracy. This seems to be a valid criticism and is backed up by machine rest tests I have conducted of identical barrels (same manufacturer but half chrome lined and half not).
As you are aware most barrel "wear" is in the throat area. So eventually the hot gasses from the burning of the gunpowder will eat thru the chrome lining at the throat. It is rumored that at this point accuracy will plummet but I have not found that to be true. (Or if true, it is overstated or maybe only occurs for that short period when there is both chrome and bare steel in the throat simultaneously - just at the point of initial break thru.) Chrome lined barrels can continue to shoot well for thousands of rounds after the bare barrel steel at the back of the barrel (throat) has been exposed due to erosion of the chrome lining. Another criticism of chrome lining is that it can flake off later in the life of the barrel resulting in poor accuracy. Obviously, this could also cause maintenance problems if the user is depending on the chrome to ward off corrosion and thus is careless in his bore cleaning. If corrosion is allowed to occur pitting will result and that will ruin accuracy for sure.
Barrel pitting was one of the reasons I got involved in Salt Bath Nitriding. I was loosing nearly as many expensive match grade barrels to improper maintenance (causing pitting) as I was to wear out. This was under the relatively benign target shooting conditions. Obviously given the reputation of degraded accuracy, using chrome lining wasn't an option. So for the past couple of years I have been Salt Bath Nitriding all of my match barrels and haven't had a single one exhibit any pitting. During that 2 yr. period shooters have put anywhere from a few hundred rounds to thousands of rounds on said barrels. I don't know how long the coating will persist so at this point I am still evaluating it as a preservative. I don't know what will happen in another year or two when these barrels get more wear on them. Salt Bath Nitriding goes on both inside of the bore and on the outside surface. So, instead of 2 manufacturing steps you have combined them into one. Salt Bath Nitriding doesn't degrade accuracy one iota, unlike chrome lining. This was the first thing that I verified when I began using the process. I broke in a bunch of barrels and then machine rest tested them for group. I recorded and kept the targets, cleaned up the barrels, and sent them to MMi TruTec for the Isonite process. When they came back I reassembled them on the same receivers with the same torque settings, same bolt carrier assemblies, same flash suppressors, etc. Then they were retested with the same ammo lots. NO degradation in accuracy and about a 1% increase in muzzle velocity.
Chrome lined barrels seem to clean up rather easily after a range session. I found the ease of cleaning of Isonite coated barrels to be similar to chrome lined barrels. The Isonite barrels clean up the easiest of any non chrome lined barrels I have ever used. Isonite can be applied to either stainless or chrome molly but the factory needs to know what steel you are sending them because the application process varies a bit. Again, I only have about 2 yr. of cleaning experience with Salt Bath Nitrided barrels. I don't know if the ease of cleaning will continue as the barrels get more rounds on them. Generally speaking, most non coated barrels get harder to clean later in life. Although stainless has a reputation of being corrosion resistant it isn't corrosion proof (I have had plenty of them return pitted) so I coat both my C.M. and my SS barrels. The Isonite on the outside of the stainless barrels cuts reflection down so my shooters like it.
I mentioned flaking of chrome lining inside the bore. Joel Kendrick is my contact at MMi TruTec, the company in Arkansas that does my Salt Bath Nitriding (they call it Isonite). He was mentioning using the Salt Bath Nitriding inside the bore prior to chrome lining it to get a better adhesion. He is currently working with one of the military contractors (maybe F.N., but don't quote me on that) relative to this process. He has given me permission to give out his contact information so I have cc'd him in my reply to you. He can give you the specifics of any testing and evaluation that has been done relative to this process and can give you quotes, etc. should you just be interested in the Isonite by itself as I use it.
One last quick note on chrome lining. Such barrels have the reputation of changing point of impact when heated up. I have found this to be very true. It may be due to the way the different metals (chrome molly and chrome) expand inside the bore. What ever the reason, it does happen and, again, this was verified on a state of the art machine rest. Isonite doesn't exhibit this characteristic.
I am sure you are well aware of some of the things I covered. Lacking specific questions, I just sort of used a shotgun approach which ended up being fairly long. If I left anything unanswered please feel free to get back to me. I have enabled my Spam Blocker to allow your e-mails to come in with out the automated hate responses that Earth Link sends out. I am sure Joel would also be glad to clarify the technical aspects of the Salt Bath Nitriding process. So far I am very pleased with it.
Best of luck!
Pete Wass
Well-known member
I had one done
Several years ago now I had a 30-284 Short done. I will concur that there was no degradation in accuracy and the barrel showed no sign of wear when I sold the rifle. I have been tempted to try a Rimfire barrel, hoping the coating would keep the pitting at bay for awhile longer, if not at bay forever. If the pitting could be stopped, a Rimfire barrel could last indefinitely.
Pete
Several years ago now I had a 30-284 Short done. I will concur that there was no degradation in accuracy and the barrel showed no sign of wear when I sold the rifle. I have been tempted to try a Rimfire barrel, hoping the coating would keep the pitting at bay for awhile longer, if not at bay forever. If the pitting could be stopped, a Rimfire barrel could last indefinitely.
Pete
Butch Lambert
Active member
Remember Pete, it is not a coating.