It's my first time turning necks to clean up high spots and minimize runout. I purchased the K&M and using the power drill to neck turn. I have read the instructions and a few links on the net. I just have one question. I read that you need to use a full sizing die to be able to size all the way to the shoulder because a bushing sizing die won't be able to. There will be a possible doughnut at the bottom of the neck where it meets the shoulder if I do not use a full sizing die ( non bushing). Is that correct? Of course after sizing I use a mandrel before neck turning. Then after neck turning run the cases through a tumbler and neck size it after. If I am doing it wrong, please let me know. Thanks for any advises.
turning necks to clean high spots
- Thread starter TackDriv3r
- Start date
Ledd Slinger
Silver $$ Contributor
Sounds good, except a FL sizing die with bushings like a Redding Type S or Whidden FL die are perfectly fine and will fully size the neck. You just don't want to use a dedicated neck sizing die. Should always bump the shoulder back a couple thou with a FL sizer to get consistent headspacing anyhow so I really don't see why anyone out there would still use just a neck sizing die.
Clean the inside of the necks really good. I use a cleaning brush, or you could tumble them. Id still run a brush in the necks tho. Makes the cases run smoother on the turning mandrel. Then FL size cases. Run cases through expander die and mandrel. Turn necks. Re-size with FL die.
If cases start getting tight on the turning mandrel even tho you have expanded them with the expanding mandrel, you probably need to anneal them
Then finally, throw your neck sizing die in the garbage. Lol
Last edited:
Thx for the info, one tricky question if I may. I used a Type S bushing die last night after turning the necks, then seating them down the neck felt good and I felt a little teeny resistance around the neck / shoulder area , could that be a doughnut under there? I am using the long 140 Hybrids in the 6.5 Creedmoor.
Won't the Type S bushing die perform well as a full length Redding full sizer or a Whidden? I thought that the ball expanders on the decapping rod on the full sizing dies tend to screw up the alignment on the necks after pulling the cases out of the die. Would that be true? Is there a better ball expander for the full sizing dies? Like a taper from Redding?
I ,yet, need to buy a full sizing die for the Creedmoor.
Last edited:
If you are going to turn necks, either turn them after they are fired (if possible) or full sized,with a standard (non-bushing) die.
Bushing dies never size the neck 100%, because of the bushing retainer shelf.
If you are going to throw your bushing neck sizing die away (really dumb advice), I'll give you my address and postage.
I have done it both ways and I agree on a FL die. My experience using a Redding FL/neck bushing die resulted in thin spots at the bushing/neck junction (where the very short unsized area of the neck met the sized portion) and after 6 firings on Lapua .308 reformed to 6.5 Creed I noticed a couple of cases that had a perforation through the neck at that junction; picture a partial case head separation and that is what it appeared like. I do anneal every firing. I cannot say for certain that using the neck bush die led to this issue but it was the only part of the process that I could see that could attribute to a 'neck separation' at that particular location.
Not sure about every neck sizing tool but mine do not size all of the neck down to the NK. shoulder junction with supplied bushings. I have made some that do. Magic mark one of your necks and run it through your sizer to see how far down it resizes. It is Correct to full length size the neck before turning it.
Before I made the post above, I remembered running the 6.5 Creed brass through a Redding neck sizer and when I ran them through the mandrel, it had very little resistance. Then on the turner the cases had a slight looseness or little wobble. So this morning I went out on my reloading table and ran a few 7 Magnum brass through a full sizer die, no bushing, and it had a lot more resistance on the mandrel, of course I used Imperial wax lube, then when put the brass on the turner rod guide, it fit like a champ, it did not have the looseness or wobble like the 6.5 Creedmoor brass had. The cuts were smoother and I figured that the full sizer die brings the neck back to SAMMI specs and the tighter fit on the mandrel pushes all the variances and doughnuts outside and you shave that off. It's my first time using the neck turner, so I need to learn my mistakes from it. Here is the pic of the cut the first time, does it need more cut into the shoulder?
http://imgur.com/a/bmWJR
http://imgur.com/a/bmWJR
On fired brass I would think you would need an actual FL die (non bushing). Personally, I turn everything while new/unfired, so that I use only the expansion mandrel. It could be difficult for FL sized necks to take a good turning mandrel fit, or it might work out well. Trial & error. Depends on your chamber, and die, and spring back, etc.
Doesn't look like you reached the shoulder yet.
Doesn't look like you reached the shoulder yet.
TackDriv3r,
It is best to turn new brass. In most cases the Neck turning tool manufacturer will offer an "expander" mandrel that is sized to work with the neck turning mandrel. They also include a die that the expander mandrel can be mounted in to be screwed into your press. The first step is to lube the expander mandrel or inside of the case neck with something like Imperial die wax if turning by hand or SINCLAIR neck turning lube if turning by power. Then run the case neck over the mandrel to size the inside diameter ID). Also be sure to use the cutter with the right angle for the shoulder of the cartridge case you are neck turning (30 or 40 degree). You have to turn the neck down to where the angle of the cutter has contacted the diameter of the shoulder to about a 1-16th to 1/8th of and inch or so. This gives the brass somewhere to flow to and prevents or at least delays the formation of a donut at the neck/shoulder junction. You will notice that the cutters point when you turn a case neck like this does not (should not) contact the neck /shoulder junction point. This is correct because you do NOT want the point of the cutter to remove metal from this spot because the brass here is thin already and you do not want to weaken it and it causes no problems. If you want to turn fired brass. Once fired is the most you should go. You will have to run your brass through a die to size the neck down before running the neck of the expander mandrel to set up for turning. If you are neck turning brass for a non-tight neck rifle. I suggest you DO NOT turn the neck wall thickness down to .0095 or below. Just turn to keep the brass as thick as you can and reduce the neck wall thickness variance to .001-.0015. Remember, when you neck turn a cartridge case for anything but a "tight neck" chamber you will reduce the case life. So keep them as thick as you can. PMA TOOL can set you up with everything you need. I would also suggest you hand turn some cases first before going the power route to get a feel for this operation. You will have to use a bushing style full-length or neck die to get the proper neck tension you need after neck turning also in most cases.
Hope this helps!
Ledd Slinger
Silver $$ Contributor
This is what a case should look like when the neck is fully turned. You have to turn down onto the shoulder if you want to avoid the brass forming a donut as it gets longer in the chamber over many firings. In which case, you will need a turning tool with a cutter that matches the angle of your case's shoulder.
Brass in the picture is not yet fireformed to it's blown out 40 degree shoulder. I have created a false shoulder so the round can be safely fired. But you can see how the neck is turned down onto where the shoulder will be after fireforming.
Brass in the picture is not yet fireformed to it's blown out 40 degree shoulder. I have created a false shoulder so the round can be safely fired. But you can see how the neck is turned down onto where the shoulder will be after fireforming.
Are you re-neck turning after fireforming to cut into the shoulder after?
Thanks folks, that is a well written advise.
Phil
Gold $$ Contributor
Ledd,
Dasher forming???
How far down the neck are you turning??
What neck thickness do you turn to for your forming???
Phil.
I don’t think anybody actually explained the complete reason for FL sizing before turning – so here goes.
Yes, sizing with a bushing die will only size part of your neck, but the real reason you need to FL size is because if only part of your neck is sized, when the cutter starts turning your neck, it will cut A LOT deeper when it reach the area not sized by the bushing because it sticks out of the neck i.e. not sized. When that happens, your neck in that area will be significantly thinner and that can lead to the neck potentially breaking off since it is much weaker in that area.
Donuts relates to how close you turn to the shoulders and is a different problem.
I understand your point of view. Thanks for the clarification.
Ledd Slinger
Silver $$ Contributor
The area turned on the false shoulder ends up on the fired shoulder because the false shoulder is set at the same point. I check them after firing and touch up the shoulders if they need it.
Ledd Slinger
Silver $$ Contributor
Ledd,
Dasher forming???
How far down the neck are you turning??
What neck thickness do you turn to for your forming???
Phil.
Not a Dasher. It's a 243 LBC T40.
I think my wall thickness is .0125" or .013", I'd have to measure again with my concentricity gauge to be sure
Upgrades & Donations
This Forum's expenses are primarily paid by member contributions. You can upgrade your Forum membership in seconds. Gold and Silver members get unlimited FREE classifieds for one year. Gold members can upload custom avatars.
Click Upgrade Membership Button ABOVE to get Gold or Silver Status.
You can also donate any amount, large or small, with the button below. Include your Forum Name in the PayPal Notes field.
To DONATE by CHECK, or make a recurring donation, CLICK HERE to learn how.
Click Upgrade Membership Button ABOVE to get Gold or Silver Status.
You can also donate any amount, large or small, with the button below. Include your Forum Name in the PayPal Notes field.
To DONATE by CHECK, or make a recurring donation, CLICK HERE to learn how.