Neck turning brass/ mandrel scarring inside neck

[nddodd]

I'm wondering if anyone else has had this problem. The mandrel on my neck turning tool is scarring the inside of my neck and the scarring is causing more resistance on my bullet seating which in return is causing my groups to open up. The only way I've found to remedy this is to run it back through the mandrel on my sizer die to kind of smooth it back out. Do yall know of a way I can avoid all this scarring. I've also got plenty of clearance between the mandrel and mouth of my cases so it's not that. It turns with no resistance, but you can tell there is some rough spots inside the neck.

Thanks,
Nathan

 

[treeman]

from what you are describeing I would polish the mandrel with 600 grit paper then with jewelers rouge then use more or different lube on necks when turning. hope this helps. Darrell

 

[500x]

Are you using the K&M 4 flute pilot by chance? If so you have to be very careful with it or it will scar. I would not recommend hitting it with the 600 grit, these turning mandrels are at a very specific size for a reason, but you can polish it. I use Imperial on the mandrel and STP/Mobil 1 mix on the cutter for lubrication. If you are not using the K&M 4 flute pilot, and if you use plenty of lube, this should be a non-issue.

 

[nddodd]

Thanks Darrel, I'll give that a try, 500x no sir I'm not using that type but I know what your speaking of.

Thanks fellas,
Nathan

 

[Webster]

I don't know if it would help but I use a bore brush to remove some of the carbon from the neck i.d. A high viscosity lube might protect the mandrel better than a low vis lube.

 

[Jim D]

I just had this same problem forming 17FB brass from military 223.
Anyway I lubed the mandrel with RCBS case lube, the water soluble kind. It worked great as when I'm done, I ultrasonic clean.

I know it's crazy but my son's name is Nathan Dodd.
Jim

 

[artbosco]

I'm wondering if anyone else has had this problem. The mandrel on my neck turning tool is scarring the inside of my neck and the scarring is causing more resistance on my bullet seating which in return is causing my groups to open up. The only way I've found to remedy this is to run it back through the

mandrel on my sizer die?

to kind of smooth it back out. Do y'all know of a way I can avoid all this scarring. I've also got plenty of clearance between the mandrel and mouth of my cases so it's not that. It turns with no resistance, but you can tell there is some rough spots inside the neck.

Tony Boyer in his new book The Book of Rifle Accuracy, on page 148, covers how to handle these type scratches by saying that he polishes the insides with very fine wet/dry, 600 to 1000 grit sandpaper by rolling up a 1/2 inch strip onto the BARE end of a Q-tip shaft and taping the inward end in place. Hold it inside the case neck [for a few seconds per case] while the case holder turns. I tried it with a portable power screwdriver turning at 180 RPMs and it worked great.

Another problem you could run into that's causing these scratches, is brass building up on the turner pilot. If that happens use some fine sandpaper to remove it. You won't hurt the pilot because most of the time it's made of carbide.

 

[artbosco]

Are you using the K&M 4 flute pilot by chance? If so you have to be very careful with it or it will scar.

The cutting tips on the Pilot are very sharp. If using a portable power screwdriver, for example, slide the lubed case neck onto the lubed pilot slowly BEFORE turning on the power source. When done turn the power off, then slide the lubed case neck off the Pilot. This procedure will prevent a lot of scratches.

 

[artbosco]

I don't know if it would help but I use a bore brush to remove some of the carbon from the neck i.d. A high viscosity lube might protect the mandrel better than a low vis lube.

Some of that carbon, believe it or not, can and does act as a lubricant and make seating of the bullet much easier than trying to slip it into a case neck without carbon buildup. Don't remove all of it. I use an RCBS plastic neck cleaning brush that mainly removes leftover powder reside.

Also, if you clean cases with an Ultrasonic cleaner, before reloading, you best apply a dry lube to the ID of the case neck, which enhances seating too.

 

[nddodd]

Thanks fellas y'all are awesome I'll deffenitly try the q-tip thing. Jimd it's most certainly a small world, that's the first Nathan Dodd other than myself of course I've heard of that's pretty cool. Thanks again guys,

Nathan

 

[alf]

Another trick I use, in conjunction with lube, is to pour a nickle size puddle of liquid Flitz on the work bench and touch just part of the case mouth in the Flitz before turning.

 

[Jim D]

I always have an old tooth brush that I use to clean the cutter and lube the pilot.
Jim

 

[bigedp51]

Lube the mandrel with oil

The article on this is at our own web site.

Complete Precision Case Prep

http://www.accurateshooter.com/technical-articles/reloading/complete-precision-case-prep/

Method: Use a K&M neck turner with a cordless drill and a K&M, Sinclair, or Hart shell holder. Start the case neck onto the mandrel of the turner. Apply a small amount of light oil to the mandrel and the case neck. TIP: When the neck is off the turner, allow the drill to continue turning the case while you wipe the outside with a paper towel or cloth. Use a cue tip inside the neck while the drill is turning to wipe the inside of the neck.

 

[nddodd]

Man fellas I sure do appreciate it, I guess the flitz acts as a lubricant where can you get some of this stuff. Where can a guy find some dry imperial sizing wax (I think it's called that).

Thanks again,
Nathan

 

[artbosco]

Where can a guy find some dry imperial sizing wax

Take your choice, but get the larger tin: http://www.google.com/search?q=Imperial+sizing+die+wax&ie=utf-8&oe=utf-8&aq=t&rls=org.mozilla:en-USfficial&client=firefox-a#q=Imperial+sizing+die+wax&hl=en&client=firefox-a&hs=U4i&rls=org.mozilla:en-USfficial&prmd=ivnsfd&source=univ&tbs=shop:1&tbo=u&sa=X&ei=aht0TbTXDoP68AaAudSYDw&ved=0CEkQrQQ&biw=1360&bih=608&bav=on.2,or.&fp=7e590312125e0dea

 

[nddodd]

Hey Bigedp51 this is a dumb question but how does the shell holder hold the case still I figured it would just spin freely inside the shell holder. My reason for asking is I'm very interested in buying the k&m Power adapter with shellholder.

Thanks again,
Nathan

 

[bigedp51]

Hey Bigedp51 this is a dumb question but how does the shell holder hold the case still I figured it would just spin freely inside the shell holder. My reason for asking is I'm very interested in buying the k&m Power adapter with shellholder.

Thanks again,
Nathan

Nathan

I do not use the K&M power adapter and I'm a little old fashioned, I turn my necks by hand to get better feel while turning the necks.

The reason I linked the web page and pasted the photo was to show you the small oil bottle with a needle applicator that was used in the article.

A lathe uses oil when turning and cutting metal, I place a drop of oil on the mandrel so the neck will "float" on the oil and not contact the mandrel and cause galling like you are getting. I also make sure the cutting edge is oiled also, after turning the necks I remove all traces of the oil with a solvent.

I also use a Sinclair neck expander on the "inside" of the necks and remove the "excess" from the outside of the neck with the neck turning tool. If you do not expand the necks and make them a uniform size they might be a tight fit on the cutting mandrel and thus cause galling and the brass build up on the mandrel you are getting.

Read the article I posted and you will not have any more problems.

 

[TonyR]

The Hart case holder has a pin that screws up through the hole in the shell holder and clamps the rim in place. The others probably work the same. The Hart case holder requires Redding shell holders. The hole in RCBS shellholders is too small for the pin the get through.