Neck turning shoulder too deep?

[David247]

This is my first time turning necks. I am using a 21st Century lathe. The instructions say to adjust the length and depth of cut so that the cut only goes up the neck .030", and when you run your finger nail across the case shoulder it should not catch on anything. I think I am good but I wanted confirmation from others who are familiar with it.

FYI, This is a Lapua 6.5 Creedmoor case and the necks were running between .0135 to .0150 so I turned them to .0130. If I adjust the depth of cut any less I get uncut places and I believe that my length of cut going up the shoulder is correct. Does it look right to you guys?

 

[22DASHER]

That is darn near perfect. I usually go just a tiny bit further.

 

[Comrade Terry]

This is my first time turning necks. I am using a 21st Century lathe. The instructions say to adjust the length and depth of cut so that the cut only goes up the neck .030", and when you run your finger nail across the case shoulder it should not catch on anything. I think I am good but I wanted confirmation from others who are familiar with it.

FYI, This is a Lapua 6.5 Creedmoor case and the necks were running between .0135 to .0150 so I turned them to .0130. If I adjust the depth of cut any less I get uncut places and I believe that my length of cut going up the shoulder is correct. Does it look right to you guys?

View attachment 1075679 View attachment 1075683

Very nice.

 

[jds holler]

Heck, I'm jealous. jd

 

[David247]

That is darn near perfect. I usually go just a tiny bit further.

Does the cut in the shoulder help prevent the donut?

 

[Comrade Terry]

Does the cut in the shoulder help prevent the donut?

Yes. That's why it's done. Other than that, there's no purpose to it.

 

[BoydAllen]

You are fine. The main thing for doughnut prevention is to have a good handle on shoulder bumping. Remember that the ONLY reason for bumping is to create clearance, and that for most once fired brass, and maybe even after a second firing, there is very likely to be enough clearance so that you can set your die to give the shoulder to head dimension of the fired case, and the cases will chamber just fine. Sometimes I think that fellows end up bumping when there is no need and that will decrease the number of firings it takes for doughnuts to form.

 

[Tommie]

Terrible. Better send all that ruined brass to me.

 

[Dusty Stevens]

If you get small uncut places its fine when just trying to uniform necks. As long as the cutter goes all the way around in some places thats perfect and considered the minimum amount for uniforming necks and not turning to a specific diameter

 

[carlsbad]

This is why I hate neck turning--trying to make that exact juncture consistent from case to case.

 

[Dusty Stevens]

This is why I hate neck turning--trying to make that exact juncture consistent from case to case.

If you get the correct angle cutter and have a neck turner with a good solid stop on it that you keep lube build up off of it- that makes it alot easier

 

[mikecr]

This is why I hate neck turning--trying to make that exact juncture consistent from case to case.

You can clearly see where to stop. No hard stop is needed, nor more accurate than visual with new brass,, and we get along just fine with that.
No cutter angle will match new brass either. That's ok, as long as it's not shallower (leading to a dig-in).
Basically, it's not rocket science. We're not trying to turn neck-shoulder junction to an exact same thickness as the neck. Just touching off a bit that would end up in donut otherwise. And it's not like it HAS to be done. Do it if you want, or when you've practiced turning for a while & comfortable with your control.

OP's pictured case looks good. After turning a handful of culled cases anyone should be able to match this with ease.

 

[David247]

You can clearly see where to stop. No hard stop is needed, nor more accurate than visual with new brass,, and we get along just fine with that.
No cutter angle will match new brass either. That's ok, as long as it's not shallower (leading to a dig-in).
Basically, it's not rocket science. We're not trying to turn neck-shoulder junction to an exact same thickness as the neck. Just touching off a bit that would end up in donut otherwise. And it's not like it HAS to be done. Do it if you want, or when you've practiced turning for a while & comfortable with your control.

OP's pictured case looks good. After turning a handful of culled cases anyone should be able to match this with ease.

With the 21st Century lathe, I had only one culled case. Then I adjusted it back a little and came back forward little by little until I got the above result. Doing what the instructions say was easy and fast. Hats off to the folks at 21st Century. I would love to get one of their self powered lathes. After turning a couple hundred necks, my hand had a cramp and my back was stiff from sitting in the same position and holding my drill. Or just do 100 at a sitting. I tried to get up and stretch a little but I get so possessed when I am focused on something that even pain doesn't stop me. I swear sometimes that shooting is just something you have to do so you have more reloading to get back to.