Have you had any experience with "cold welding" of bullets in case necks?
- Thread starter BoydAllen
- Start date
BoydAllen - I would agree that one does not have to know what is happening to prevent it – in many ways that is my own approach. Knowing the mechanism does have some advantages since it allows you a better understanding and perhaps to devise a elegant method to prevent it from happening, but that may be academic in nature.
22XC Guy - The problem is not so much the detection of the welding/adhesion (depending on whether we are talking about cold welding or corrosion), this can be easily detected since one can test the bullet/case immediately after putting them together and before anything can happen to get a baseline value. Any significant increase in this value later in a consistent manner will tell you something is happening. The problem is figuring out what is actually happening to change this value.
22XC Guy - The problem is not so much the detection of the welding/adhesion (depending on whether we are talking about cold welding or corrosion), this can be easily detected since one can test the bullet/case immediately after putting them together and before anything can happen to get a baseline value. Any significant increase in this value later in a consistent manner will tell you something is happening. The problem is figuring out what is actually happening to change this value.
I’m not ruling out cold pressure welding, the principle and applied technique has a fine line between either bonding or a corrosion starting point. Welding in minutes verses corrosion in hours or mpy, mills per year.
I’m tossing this out there from my experience, steel wool cleaning could be cross contaminating the case neck surface with low iron/carbon content, plus adding solvent cleaning residue/reaction, and keeping in mind of reloading handling and storage.
Is bullet core material completing the dissimilar cycle, from looking at the material alignment, maybe.. I’m not sure what the content/mixture is.
Several factors could be accelerating [seizing] resistance from contact corrosion, induced galvanic series/corrosion, or slight dezincification/residue on a molecular level or the residue was actully visible. I can't tell from the pictures that were posted, but I see tale tail on bullet picture.
The attached links are highly used in the refineries for technical corrosion/erosion prevention, but the levels of application are more severe under atmospheric service and conditions.
7 more pages and team work will have this root cause analysis completed.
http://events.nace.org/library/corrosion/MatSelect/corrbrass.asp
http://events.nace.org/library/corrosion/Forms/dezinc.asp
I’m tossing this out there from my experience, steel wool cleaning could be cross contaminating the case neck surface with low iron/carbon content, plus adding solvent cleaning residue/reaction, and keeping in mind of reloading handling and storage.
Is bullet core material completing the dissimilar cycle, from looking at the material alignment, maybe.. I’m not sure what the content/mixture is.
Several factors could be accelerating [seizing] resistance from contact corrosion, induced galvanic series/corrosion, or slight dezincification/residue on a molecular level or the residue was actully visible. I can't tell from the pictures that were posted, but I see tale tail on bullet picture.
The attached links are highly used in the refineries for technical corrosion/erosion prevention, but the levels of application are more severe under atmospheric service and conditions.
7 more pages and team work will have this root cause analysis completed.
http://events.nace.org/library/corrosion/MatSelect/corrbrass.asp
http://events.nace.org/library/corrosion/Forms/dezinc.asp
22xc guy, I can believe that the steel wool could cause the problem that some have. It may be a good idea to switch from steel wool to Bronze or stainless wools. I do use steel wool inside the neck to start with to polish the rough interior of the neck but i also blow out the case with air and use a nylon brush after that. the only steel wool that his the case is the chamfer on the case mouth. The steel wool and brass copper and a chemical added to the mix, you may be on to something. I have never seen it but i may stop the use of steel wool........ jim
bozo699
Gold $$ Contributor
johara1 said:
Jim,
I wasn't going to reply to this thread anymore but what you have said hit the nail on the head at least in my case, On a tight chamber I light outside neck turn, fire form and finish getting my neck clearance I want by inside reaming, I have found at least for me this gives me the most consistent neck thickness, I have done this for three separate chamberings, the 6*284 that I mentioned to Boyd about, the Dasher and my newest BR rifle the 6BRX after I inside ream I polish with 0000 steel wool, that is when I found the trouble with the "POP" the first time, I didn't blow the steel wool debris out of the case and didn't brush, ( didn't know any better ) I have had it happen on the Dasher and 6BRX as well, I was telling this to Tom Mousel and Leo Anderson and they both told me the key was to brush the necks (VIGOROUSLY) with a nylon brush, I have not ever had the problem since I started brushing my necks with a nylon brush, I now anneal after each firing, there is a scale left behind and if I don't brush with the nylon brush before seating I have a harder time seating the bullets (more force) so brushing is now just part of my reloading regime, I believe it to be KEY to consistent and equal seating tension,...JMHO's and $.02 worth.
Wayne.
P.S as I have stated before I am not a rocket scientist and FOR SURE don't want to be so I don't know if it is cold welding, corrosion, dissimilar metal bonding, contamination, or the reloading Gods putting voodoo hexes on certain people's bullets I just know it can and occasionally DOES happen!
Jim,
That was one reason why I tossed in steel wool; brass is a tough alloy up to a point until something changed. I never experienced any usual problems at work, but stainless steels and welding is susceptible iron/carbon contamination from using the carbon steel, hammers, grinding discs, brushes etc causes a localize corrosion cell/s.
That was one reason why I tossed in steel wool; brass is a tough alloy up to a point until something changed. I never experienced any usual problems at work, but stainless steels and welding is susceptible iron/carbon contamination from using the carbon steel, hammers, grinding discs, brushes etc causes a localize corrosion cell/s.
22xc and Wayne , After looking in my cases after using steel wool with a bore scope i did see some steel particles left behind and after annealing seeing what is in the neck, to put it simply loading a bullet in sand paper. I started using a stiffer nylon brush that is blue and sold by midway. I still use air and yes i have a dryer on air line. No chemical cleaning and no problems so far............jim
I noticed last night polishing Lapua brass with a green scrubbie pad with the cases chucked up in a drill and case holder and spinning fast that there were clearly alot of shiney brass pieces embedded in the green pad and I was pretty amazed at how abrasive that stuff is and maybe it would substitute for you guys having problems with steel wool shavings in your cases.
A bit of Ballistol and 5 seconds spinning in the green pad and those suckers were as ever.
A bit of Ballistol and 5 seconds spinning in the green pad and those suckers were as ever.
BoydAllen
Gold $$ Contributor
A little added info that might help some of you:
I have been working with some new cases for my 6PPC, Norma, as part of the prep process, I lubed the inside of the necks with a wax and water based lube that The Woodchuck Den (Todd Kindler) sells. The reason that I bring it up here is that after application it dries, so that powder does not stick in the necks. I used the stuff to lube before expanding. (This is 6PPC brass, with necks that are thinner and softer than Lapua .220 Russian, so there was not a lot of increase in neck diameter needed to turn.) and then touched them up with a smidge (note: ft. lb. system smidge, as distinct from metric smidge) for turning, that went well.
If you are having to scrub your necks to bright metal after annealing, to remove the rough oxidation, then you might find this stuff useful as a fast and easy way to put something in the necks to prevent subsequent "cold welding" (or whatever your preferred term is) Of course, if your load requires a lot of bullet pull, you should probably look elsewhere.
The stuff comes in a little flip top plastic tub, and has doomed me to convert to some religion that believes in reincarnation, since it appears that given how little is required to do the inside of a neck, I have enough to get me through several long lifetimes.
I have been working with some new cases for my 6PPC, Norma, as part of the prep process, I lubed the inside of the necks with a wax and water based lube that The Woodchuck Den (Todd Kindler) sells. The reason that I bring it up here is that after application it dries, so that powder does not stick in the necks. I used the stuff to lube before expanding. (This is 6PPC brass, with necks that are thinner and softer than Lapua .220 Russian, so there was not a lot of increase in neck diameter needed to turn.) and then touched them up with a smidge (note: ft. lb. system smidge, as distinct from metric smidge) for turning, that went well.
If you are having to scrub your necks to bright metal after annealing, to remove the rough oxidation, then you might find this stuff useful as a fast and easy way to put something in the necks to prevent subsequent "cold welding" (or whatever your preferred term is) Of course, if your load requires a lot of bullet pull, you should probably look elsewhere.
The stuff comes in a little flip top plastic tub, and has doomed me to convert to some religion that believes in reincarnation, since it appears that given how little is required to do the inside of a neck, I have enough to get me through several long lifetimes.
BoydAllen
Gold $$ Contributor
I would think that once a month, waiting about three months to start testing would be more realistic. How doe that go about a watched pot? I think that I may have some old reloads around somewhere. I will look tomorrow, and if I do, I will try seating a few bullets a little deeper.
alf
Silver $$ Contributor
All right, here's my take.......
I just broke down 63 rounds of 6 Dasher that were loaded a year ago on 4-30-11. They were loaded with moly plated 107 SMK's in brass that had been shot 13 times, but annealed every time, including the last loading.
The first 8 I re-seated with my Wilson seater in the arbor press, and there was absolutely no "pop" or any indication of cold welding. I then removed the bullets with Sinclair's plier type bullet puller in the press, and they slid right out without any undue pressure.
I then went to removing the bullets without re-seating first, and could tell no difference in the tension to pull the bullets from these cases.
I ended up re-seating about half total, and would alternate between the two to get a good take on both. I couldn't detect any difference.
Now I see why, with my loading techniques, that it doesn't matter when I load my match ammo, whether it's one day, one month, or one year before the match.
I just broke down 63 rounds of 6 Dasher that were loaded a year ago on 4-30-11. They were loaded with moly plated 107 SMK's in brass that had been shot 13 times, but annealed every time, including the last loading.
The first 8 I re-seated with my Wilson seater in the arbor press, and there was absolutely no "pop" or any indication of cold welding. I then removed the bullets with Sinclair's plier type bullet puller in the press, and they slid right out without any undue pressure.
I then went to removing the bullets without re-seating first, and could tell no difference in the tension to pull the bullets from these cases.
I ended up re-seating about half total, and would alternate between the two to get a good take on both. I couldn't detect any difference.
Now I see why, with my loading techniques, that it doesn't matter when I load my match ammo, whether it's one day, one month, or one year before the match.
I think 300 RUM is doing the right experiment, test some with short time period to get the baseline control values, wait variable periods and test the others.
Alf – If my read on cold welding is correct, you are never going to get it using moly plated bullets. Cold welding requires both surfaces which are to be welded together to be of the same i.e. brass, absolutely clean, and smooth. That moly acts as an interference layer between the brass and makes this impossible.
Alf – If my read on cold welding is correct, you are never going to get it using moly plated bullets. Cold welding requires both surfaces which are to be welded together to be of the same i.e. brass, absolutely clean, and smooth. That moly acts as an interference layer between the brass and makes this impossible.
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