second neck turn

[hairtrigger]

I have been following the article on case prep here in the article archive section. I have fired a lot of 350 cases twice and was going to run them through the neck turner again just to do a final clean up. First I body sized, bumped the shoulder back .002, and retrimmed. I ran all cases through the Redding neck sizer with my largest bushing and then back over the K & M mandrel. When I turn the necks it seems that an inordinate amount of material is being cut off the neck below the limit of sizing bushing and the shoulder junction. I assume that this is because this area is larger due to not being sized.

How should I proceed? I’m a little concerned that I may be taking too much at the neck shoulder junction as on the new case cut I cut in as indicated in the article. Thanks in advance for any help.

 

[StephenPerry]

HT
You are ok here. I don't use a K&M but I assume it has a radiused cutter head on the turner. This will allow you to move into the shoulder area without damage to the junction. Move into the junction only far enough to cut a minimal amount into the shoulder.If you are within a half thou of your desided OD now run the trimmer 1 more time slowly with the same setting to get a skim cut. Everything should come out smooth to the touch and now you will be at your desired OD.
When cutting turn in the same direction on and off the neck. Use a small brush to clear the chips. I use Imperial Sizing Die Wax on the neck and the mandrel but most will work fine. Make sure your case holder is xtra tight so the case doesn't slip.
Stephen Perry

 

[mikecr]

I think you need to get the neck parallel with the turning mandrel. Otherwise your reducing thickness based on SHAPE.
If for some reason, you really feel that more turning is needed, you may have to use some ingenuity to get the necks straight-shaped enough for turning. Do you need further turning?
Is the neck brass thicker near the shoulder? This was turned already, right?
You may have to fully size the necks, well below cal, and then expand in steps to form out the taper in your necks.
This is where Sinclair's mandrel system is superior to pulling expanders.

If the taper was formed due to taper in the chamber neck, I would not bother with all this, if I were you. Only one turning is needed. before the brass is fired.

 

[anyrange]

Hair Trigger,
You are correct, there is a small area not resized at the base of the neck and you may over cut or thin that area to much. I also use a normal full sizing die before neck turning for that exact reason, it sizes the whole neck. Then trim case length so neck cutting length is same on all.

 

[Forum Boss]

Ken of K&M recommends using a conventional full-length sizer,that does the WHOLE neck) before turning the necks. His tool,and most others) will perform better with a "crisp" neck-shoulder junction. As others have noted, a neck-sizer tends to allow brass to thicken and form a coke-bottle-neck style radius at the neck shoulder junction.

 

[hairtrigger]

Thanks for all the responses. I have only been chasing the precision reloading for a year now although I have been shoving bullets into cases for 30 years. I still have a lot to learn, and all of you have helped greatly.

I guess I really do not have to neck turn again, but was trying to follow the guidelines set in the article on case prep here. I think I have some good cases going, and was trying to get them as good as possible.

Next call to Sinclair I will get a full length sizer. I have been working with a Redding bushing neck sizer, body die, and the Reddding competition seater. I use a Forster Co-Ax press. I would have to imagine that I do not want a bushing style, but rather a solid body with a fixed neck. Or should I order a fixed neck die ground to my sizing diameter?

Mikecr: Yes I did turn into the shoulder on the initial turning,new brass) and after fire forming the dimension to the datum line is greater than it was with the new brass which was what I expected. All these rounds are for the same rifle so I neck sized only after the first two firings and ran the body die this time not because there was a chambering problem but because I wanted to re trim and re turn the necks and get back to a level spot with everything. I would like to know more about the Sinclair mandrel as opposed to the expander button if you have time to elaborate.

What I’m trying to here is learn to be the best handloader I can. I am not a benchrest shooter, but an avid varmint hunter and I believe by emulating the benchrest techniques I will get the best accuracy possible. Any suggestions are welcome and appreciated and if I am doing something wrong please advise. I’m real good at constructive criticism; I’ve been married for 33 years.

 

[mikecr]

Sinclair neck turning mandrels fit in a mandrel die they offer. You load your die with the right size mandrel and expand your necks from the top, using your press. Since there is no pulling expansion from the bottom as with K&M, there is less chance of ending up with tapering of the neck diameter. Also, less runout formed. These mandrels are available in 'turning' and 'expander' diameters for 17-33cal, which is great combined with Redding bushings for forming about anything you want.
It's vital for initial forming/turning with brass that is thicker or thinner than usual,like WSSM). It's good for pushing any thickness variance outward prior to seating bullets,reducing runout at the ogives).Buy the whole set, and you'll use them the rest of your reloading days. Wait a minute, only I am crazy enough to do that.

I may be missing something important, as I never turn after firing. I do turn all my brass, tight chamber or not. But always before firing. My brass has always come out correct after firing, and I'm a stickler for runout. No surprises yet...

I don't have actual redding bushing dies, but it seems like I've stacked bushings with my customs to get full depth neck sizing with long neck cartridges. Try that before investing alot.
Put any oversize bushing on top of your correct bushing, and screw the plug down. If any of your bushing dies have an expander on the depriming stem, get rid of them or disable them. First thing I do with a die is toss them, as expansion with bushing dies is not normally needed if you choose the right squeeze.
Anyway, mess with it. Now is an opportunity to really see whats going on with your brass.

 

[Preacher]

Mike,
Can you go into a little detail about this statement you mentioned......
-------------------------------------------------------------------------
, Since there is no pulling expansion from the bottom as with K&M, there is less chance of ending up with tapering of the neck diameter)
-------------------------------------------------------------------------

I use a K&M press adapter that screws into the top of my A-2 press with the correct mandrel and it goes into the top of the case neck
and irons out and slightly expands the neck before I turn the necks, and I can't quite figure out what you mean about the difference between this tool and the Sinclair tool seeing that they both do the same thing ??
K&M's mandrels go from 17 to 338 also.