PSA regarding mandrels...

ZA206

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Minuteman
Jan 24, 2014
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Just a heads up/PSA... if using a mandrel with a Ti-N (gold) coating that's advertised as "not needing lube", disregard that advertisement.
Lube IS required.

This past weekend I expanded the necks on maybe 150 pieces of 6.5CM brass that had been wet tumbled and annealed. I didn't lube the necks during expansion just to see if it mattered. Yep. Expanding force was increased, and most importantly, at the end, it looked like there were streaks of galled brass running up the mandrel and it was very rough. I wrapped it in a cotton patch and hosed it down with Patchout & Accellerator and left it in the sink overnight. Patch was blue and purple the next morning, but was clean as a whistle and smooth again. Lesson learned.

No experience with the carbide versions or the "black" one from 21st Century, feel free to chime in.

Chime in with your experiences...

-ZA
 
I generally skip specifically lubing the necks but I walnut tumble, so it leaves some carbon in the necks. I've never had to de-gall the black nitride doing this, but a standard stainless needs to be cleaned up after 100 cases or so. If running a custom diameter, it's hard (or very expensive) to get anything other than stainless finish.
 
Just a heads up/PSA... if using a mandrel with a Ti-N (gold) coating that's advertised as "not needing lube", disregard that advertisement.
Lube IS required.

This past weekend I expanded the necks on maybe 150 pieces of 6.5CM brass that had been wet tumbled and annealed. I didn't lube the necks during expansion just to see if it mattered. Yep. Expanding force was increased, and most importantly, at the end, it looked like there were streaks of galled brass running up the mandrel and it was very rough. I wrapped it in a cotton patch and hosed it down with Patchout & Accellerator and left it in the sink overnight. Patch was blue and purple the next morning, but was clean as a whistle and smooth again. Lesson learned.

No experience with the carbide versions or the "black" one from 21st Century, feel free to chime in.

Chime in with your experiences...

-ZA
This likely has as much to do with your wet tumbling as anything else. IMO, inside the neck lube is part of a process for consistency, but techniques vary and I don’t think that there’s ever only one way to achieve that.
 
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When I resize and mandrel 223 brass, I'm using homebrew lanolin lube that's sprayed in most of the necks (basically hosed down... LOL) and the whole mandrel deal goes really smooth. Once resized and mandreled, they get tumbled in corn cob for final cleanup. On my 6.5CM brass, I typically use Imperal wax lube and just wipe it off afterwards.... hence no lube in the necks unless I specifically dip them in dry lube (my normal procedure).
 
Just a heads up/PSA... if using a mandrel with a Ti-N (gold) coating that's advertised as "not needing lube", disregard that advertisement.
Lube IS required.

This past weekend I expanded the necks on maybe 150 pieces of 6.5CM brass that had been wet tumbled and annealed. I didn't lube the necks during expansion just to see if it mattered. Yep. Expanding force was increased, and most importantly, at the end, it looked like there were streaks of galled brass running up the mandrel and it was very rough. I wrapped it in a cotton patch and hosed it down with Patchout & Accellerator and left it in the sink overnight. Patch was blue and purple the next morning, but was clean as a whistle and smooth again. Lesson learned.

No experience with the carbide versions or the "black" one from 21st Century, feel free to chime in.

Chime in with your experiences...

-ZA
The carbine "black" nitrided one needs lube too. After 100 cases the nitride coating looks like this. Works just fine but I am using the Moly/Media from them.

1707440985505.png
 
Remember... correlation is not causation.

I've got something like ~10k rounds on a .241" Sinclair TiNi "turning arbor" (mandrel) and stopped using lube with it right around the time I also stopped wet tumbling precision rifle cases (like ~8-9k rounds ago) ...no issues here.

I do not clean my cases after firing, fired brass sees an AMP, gets sprayed with 1:10 Lanolin/IPA mix, then gets sized and decapped in one step before dry tumbling all the lube off in 20-40 grit corn cob blast media before seeing a mandrel.

IMO/IME dry tumbling is 1000% better (or less harmful, if you prefer) for one's cases than wet tumbling for myriad reasons including it leaving a little dust in the necks which probably helps and acts as lube with the mandrel step... which again, I purposely do after they're out of the tumbler.

Lastly/also, I quickly/lightly chamfer the inside of my case mouths before priming and then seating bullets... "one Mississippi" or less is all it takes for them to whistle, ensuring I get every penny of the BC I paid for, and skimming the surface of the brass where it matters most (just in case lol).
 
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Which manufacturers specifically advise to use their mandrels without lube? All literature usually just states that coatings help with lubricity, but don't advise against the use of lube.

21st century specifically recommends using dry lube with all their mandrels.
 
Which manufacturers specifically advise to use their mandrels without lube? All literature usually just states that coatings help with lubricity, but don't advise against the use of lube.

21st century specifically recommends using dry lube with all their mandrels.
I’m not sure the absence of advice is the advice for absence in this case. Fielding phone calls and customer complaints are unpaid labor, and I’m guessing the makers just don’t want the hassle of dealing with people whose case prep is juuuust different enough from someone else’s to have issues. “Always use neck lube” is cheap insurance on their part.

Just my thoughts