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Best case mouth lube for accuracy?

Shinbone said:
I am wondering what people use for lubing the case mouth ID prior to seating the bullet for accuracy purposes?

Preface: Cases are annealed after each firing. The only cleaning operation I do to the case mouth ID prior to seating the bullet is to brush them out with a nylon brush (i.e. no tumbling, no ultrasonic cleaning, etc.), thus presumably leaving some carbon in place. Bullets are seated using an arbor press and a Wilson seating die.

For bullet seating, I started out using powder graphite on the case mouth ID brushed on dry with a bore mop. I also coated the bullet shank with the same dry powder using a small container of ceramic beads.

I then switched over to using moly powder for the case mouth and bullet shank, applied in the same way, and I think I noticed a slightly easier seating force.

One time, I got lazy and left the Imperial Sizing Wax in the mouth ID after an expanding operation, and for sure noticed an easier seating force, and also observed generally lower ES's. But, the ISW has obvious problems such as powder sticking to it, and the possibility of some powder contamination. But the lower ES's caught my attention, making me think that maybe there is a better way to lube the case mouth ID than what I had been doing.

I did a search on the subject. I see lots of threads for lubing the case mouth OD for sizing purposes, and some threads on lubing the case mouth ID to prevent bullet weld (for example: https://forum.accurateshooter.com/threads/lube-inside-case-mouth.4064505/), but I found pretty much nothing in regards to accuracy. I am interested in hearing what other people do to lube the case mouth ID for best accuracy?
Click to expand...
I've tried a number of things in my quest for consistent neck interference, a lot of it just trying to see what did what:

Doing the following without annealing and after a number of firings. . .
*Wet tumbling with SS pins to get squeaky clean neck interiors, then seating with minimal neck tension (no lube).
*Wet tumbling with SS pins, getting clean necks and applying Imperial Dry Neck Lube
*Wet tumbling with SS pins, getting clean necks and applying a little Imperial sizing was Lube
*Wet tumbling with no media leaving some carbon on neck interior
*Dry tumbling with rice before and after sizing
*Clean necks outside only with steel wool, size with Imperial sizing wax and dry tumble with rice
*Doing all the above but after annealing

Not having custom barrels, I've found that the first major improvement was annealing my brass, and I do it after ever firing now. This alone produced the most noticeable seating improvement for me, as the sizing movement in the necks were large resulting in work hardening where neck interference would increase. That's not an issue any longer, now that I anneal after every firing.

In addition to that my best results has been when dry tumbling with rice after FL sizing with Imperial Sizing Die Wax. The exterior of the cases feel like they've been polished and the seating feels like it's been lubed, though there's still carbon residue left on the inside. I get really consistent seating feel when seating with my L.E. Wilson seating dies and it shows up in my stats as I get pretty consistent SD's in the mid single digits, which I'm very happy with. So, I'm sticking to that above bolded part of my current procedure. I just haven't tried or heard of anything that works better.

BTW: Because I only process 100 cases or less at a time, cleaning the necks with steel wool after annealing isn't much of a chore at all, even with my very old hands. ;)
 
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I have a bolt 20 Vartarg, and recently acquired 20 Practical bolt gun too, but I've never used moly on bullets in anything. I don't have a tumbler, just the ultrasonic, so I think I'll do some testing with the Neolube and my normal loads on both, see if it still likes my earlier loads, and if they have lower SD's and ES. I got some tiny foam tipped applicators off Temu for applying the lube, but haven't tried it yet. I only have 1000+ cased to do when I get it figured out! :D
 
Shinbone said:
I am wondering what people use for lubing the case mouth ID prior to seating the bullet for accuracy purposes?

Preface: Cases are annealed after each firing. The only cleaning operation I do to the case mouth ID prior to seating the bullet is to brush them out with a nylon brush (i.e. no tumbling, no ultrasonic cleaning, etc.), thus presumably leaving some carbon in place. Bullets are seated using an arbor press and a Wilson seating die.

For bullet seating, I started out using powder graphite on the case mouth ID brushed on dry with a bore mop. I also coated the bullet shank with the same dry powder using a small container of ceramic beads.

I then switched over to using moly powder for the case mouth and bullet shank, applied in the same way, and I think I noticed a slightly easier seating force.

One time, I got lazy and left the Imperial Sizing Wax in the mouth ID after an expanding operation, and for sure noticed an easier seating force, and also observed generally lower ES's. But, the ISW has obvious problems such as powder sticking to it, and the possibility of some powder contamination. But the lower ES's caught my attention, making me think that maybe there is a better way to lube the case mouth ID than what I had been doing.

I did a search on the subject. I see lots of threads for lubing the case mouth OD for sizing purposes, and some threads on lubing the case mouth ID to prevent bullet weld (for example: https://forum.accurateshooter.com/threads/lube-inside-case-mouth.4064505/), but I found pretty much nothing in regards to accuracy. I am interested in hearing what other people do to lube the case mouth ID for best accuracy?
Click to expand...
Mobil 1 Tommy mc
 
whatsupdoc said:
Strange thing is that some of my lowest SD/ES numbers have been with brand new cases with just a
mandrel pushed through the neck.
Click to expand...
Not a popular view around here, but there are enough folks in HP, F-Class, PRS, etc., who run this way to say it isn't rare or strange. It works for them.
The Pros and Cons with only using virgin brass to compete, is they have to stay stocked up or they find themselves needing to re-cycle their brass. That used to be easy, but since the elections and Covid, that can be a challenge.
 
TheCZKid said:
Erik Cortina says he no longer cleans his brass, says it's a waste of time, and shows no difference in accuracy. He uses the carbon left in the necks as his lube.
Click to expand...
Actually, he DOES clean his brass, if you count using a rag to hand wipe each individual case to remove the sizing wax. One at a time. Do that for 1000 pieces of rifle brass, and then tell me that's easier or better than tossing those lubed cases in the tumbler for 30 or 60 minutes while you eat a sandwich or clean your barrel. It's just a bragging thing to say "I don't ever clean my brass". Another user here today said he also never cleans his brass but every third firing he uses a rag with acetone to wipe each individual case neck.

So there you have it, WIPE cleaning is superior to tumble cleaning.

Also, wiping case necks with a rag and chemicals to clean carbon off the necks is not to be confused with cleaning. It's simply wiping.

Like saying I don't chase the lands, I just adjust the seating depth every once in a while as the lands erode. It's different.
 
whatsupdoc said:
Strange thing is that some of my lowest SD/ES numbers have been with brand new cases with just a
mandrel pushed through the neck.
Click to expand...
So maybe the very high temperature and pressure of the burning powder charge cause micro-pitting to the case mouth ID which causes a big spike in surface friction?

Perhaps it would be best to do a polishing step to the case mouth ID before adding whatever a person's lube of choice? Maybe put some rouge on a bore mop and run it into the case mouth on a drill motor. Then wet tumble to clean.

Just thinking out loud . . .
 
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Shinbone said:
So maybe the very high temperature and pressure of burning the powder charge cause micro-pitting to the case mouth ID which causes a big spike in surface friction?

Perhaps it would be best to do a polishing step to the case mouth ID before adding whatever a person's lube of choice? Maybe put some rouge on a bore mop and run it into the case mouth on a drill motor. Then wet tumble to clean.

Just thinking out loud . . .
Click to expand...
I’m thinking definitely not
Wayne
 
I'm newish to reloading, but I feel like leaving the carbon in the neck would be the most consistent form of lubing. Once you use the nylon brush, that should "even" it out. However, how thick is the carbon to begin with? Ive tried dry lube and no lube and carbon. I feel like the carbon is the way for me anyway. Lot less work too which is nice. I also asked a very similar question awhile back.

How do you clean your brass?

First I bring the monkey inside, normally when it's really cold. Oh, wrong brass.
forum.accurateshooter.com
 
Neck bushing should control neck dia. I never use a inside neck mandrel when resizing, but do nylon brush, my seating tension is as even as you can measure. When fired my necks expand the .0015" to .002" clearance for perfect even release.

I make sure a new bullet freely passes thru my mouths after fired before resizing. Then size with .002" smaller bushing than my loaded neck dia.
 
New brass I use Imperial dry lube- just dip each bullet base in it.
After being fired, a stiff nylon brush chucked in a drill for a few sec. I don't anneal or clean, other than to wipe the sizing lube off with a micro fiber cloth.
 
I use a carbide mandrel. The only time I graphite inside the neck is the first time I load a new Lapua case. I have tested and found nothing changes with different methods. Just my experience.

Somebody asked me once if the graphite was being evenly coated.....
 
Has anyone ever compared the behavior of the carbon deposit left behind in the neck before and after annealing? Mine sure looks different after annealing. Seems to me that carbon would remain carbon after heating through annealing. IE is "carbon" the correct term for the residue inside the neck?

Hoot
 
David,
Do you load long and seat at the match?
Or do you load and call it done?
Or some of both?

Happy New Year!
 
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