What would be a good "non-contaminating" lube for mandrel in neck turning

[tonysnoo]

This question came up about a year ago and a few guys talked about ice water...a bowl of it to keep the cutter cold. I used imperial in the past, but tried the ice water trick. I dip the case neck in too so as to trap a bit of water. It worked so well. Super consistent no discoloration of the wax on the mandrel. I want to thank the guys who turned me on to good old ice water.

 

[wolley]

Just motor oil from a needle dropper. Put a drop on the mandrel everyother case. They're going back in the tumbler anyway.

 

[timeout]

Wouldn't it be better to expand them and not use lube ? Larry

If you expand the neck and not use lube, you will get galling on the turning mandrel and heat which will expand the neck and give you uneven turns.

I expand my necks .001 larger then mandrel. I don't ever get any heat and mine same on 3 difference places. The cuter cuts off the mandrel. If I have .012 between the mandrel how can it cut un even. Larry

I have had two different neck turn systems. Both had expander mandrels that were .001" larger than the turner mandrel. They both produced snug fits. I have necked up from 6MM to 30 cal and the fit can be quite snug. This produces heat, so lubrication is critical. I use the 21st Century lathe exclusively, so ice water is not an option. I am trying to understand what you mean by .012 between the mandrel? I do believe that a close and proper fit between the cartridge case neck and the mandrel is key to obtain a good finish and uniform cuts, at least with my lathe and cordless drill setup.

 

[savagedasher]

.012 between the mandrel an the cutting blade . That is how my Sinclair works Larry

 

[jlow]

Wouldn't it be better to expand them and not use lube ? Larry

If you expand the neck and not use lube, you will get galling on the turning mandrel and heat which will expand the neck and give you uneven turns.

I expand my necks .001 larger then mandrel. I don't ever get any heat and mine same on 3 difference places. The cuter cuts off the mandrel. If I have .012 between the mandrel how can it cut un even. Larry

I have had two different neck turn systems. Both had expander mandrels that were .001" larger than the turner mandrel. They both produced snug fits. I have necked up from 6MM to 30 cal and the fit can be quite snug. This produces heat, so lubrication is critical. I use the 21st Century lathe exclusively, so ice water is not an option. I am trying to understand what you mean by .012 between the mandrel? I do believe that a close and proper fit between the cartridge case neck and the mandrel is key to obtain a good finish and uniform cuts, at least with my lathe and cordless drill setup.

That's been my experience using the K&M expander that working with their turning mandrel. If you can get away with it Larry more power to you but you asked and I gave you my experience.

 

[savagedasher]

The best set up I have done is use a tight mandrel set up and dialed in a 4 jaw chuck . and turn with a lathe. The Tail stock can be used to install and remove the case. with a live center. Larry

 

[artbosco]

I use Imperial Sizing Die Wax and clean out the residue with a Q-TIP while the case is still in my powdered case holder.

Once I've Turned, I chamfer and deburr the end of the case neck, then stuff the case neck into 0000 steel wool to smooth up the chamfering and deburring and any turning imperfections, then put the Q-Tip inside the case neck while it is turning to remove the lube. Works Great and has for years, without any mess or need for solvents.

The first fire forming will take care of any microscopic residue that may have remained in the neck. Don't make the clean up process any harder than it needs to be.

 

[Joe R]

Indy Bob said:

What would be a good "non-contaminating" lube for mandrel in neck turning....

I use a Gracey neck shaver and it spins at 1,480rpm much faster than any drill I know. I was having heat issues while neck turning so I started using Petroleum Jelly (PJ). You may already have it in your house. It has a melting point of 98 degrees.

In the past I have loaded the cases without cleaning it out. It does make the bullet more slippery and it did increase my (.308 cal) velocity by 10-15 fps, but had no other issues with it.

Kindest regards,

Joe

 

[jlow]

Hi Joe,

I think a lot of stuff can be used as a lubricant, I think the concern some would have using something like PJ would be if you do not remove the material before reloading i.e. if the material was left inside the case, there is a potential that it could affect the powder adversely if the round was not used for a significant amount of time. Not saying this is the case for PJ but since this would be an unknown, probably best to be on the cautious side.