Neck donut, some advices for...

[RTTY]

... prevent or solve the issue?

I've my fired cases (6,5x47 Lapua) with donuts.

I load with Lapua Scenar 139gn and don't engage the donuts with the bearing surface.

So have some advices, trick, for prevento or solve the donuts?

Thanks, Camillo

 

[memilanuk]

 

[simonp]

Good video though one note, K&M neck turning tools cut out the donut both from the outside and inside so may be worth trying - your experiences may vary.

 

[memilanuk]

One of my K&M neck turning pilots has the carbide donut cutter on it - I think it's 6.5mm, from back in the before times when I had to 'make' 6.5-08 brass from either Winchester .308 or Lapua .243 brass and there was a fair bit of neck turning involved either way. Depending on how you did it (.243 to 6.5), donuts formed right from the get-go as the thicker shoulder material was now part of the new 'neck', at least at the base. I remember that K&M cutter left a pretty ugly interior finish - definitely needed some polishing with #0000 steel wool on a brush and a drill to clean up the surfaces after that thing got done. Then again, that was *very* early in my 'precision' reloading career, so it's entirely possible I wasn't doing it 'right'

Not sure how the surface finish left by that compares with say, the LE Wilson inside neck reamer.

 

[straightshooter1]

... prevent or solve the issue?

I've my fired cases (6,5x47 Lapua) with donuts.

I load with Lapua Scenar 139gn and don't engage the donuts with the bearing surface.

So have some advices, trick, for prevento or solve the donuts?

Thanks, Camillo

Using an expander mandrel after sizing (using no spindle with expander button) tends to move any donut to the outside. . . especially well when annealing the brass.

Turning the necks where the cutter cuts a little into the shoulder, when done correctly, will prevent growth of the donut.

If one is using a bushing sizing die, the bushing doesn't size all the way down leaving the interior ID at the neck-shoulder junction large enough where donut growth doesn't come into play.

Neck sizing with a collet die can squeeze away the donut, moving that brass material into the neck.

The donut can be cut away with a good reamer run through the neck (like the one K&M has).

Choose your poison.

 

[RTTY]

Thanks for the video/advice!

 

[RTTY]

Good video though one note, K&M neck turning tools cut out the donut both from the outside and inside so may be worth trying - your experiences may vary.

Yes the K&M are on my playlist...
But I ready se me impression of users that the internal reamers don't leave a good finishing internal surface, @memilanuk confirm the "issue"...

 

[RTTY]

Using an expander mandrel after sizing (using no spindle with expander button) tends to move any donut to the outside. . . especially well when annealing the brass.

Yes I can use and expander for the tension of the neck.
Yes I anneal my brass after a single firing.

Turning the necks where the cutter cuts a little into the shoulder, when done correctly, will prevent growth of the donut.

What angle of cutter I can choice for my 6,5x47 Lapua cases?

If one is using a bushing sizing die, the bushing doesn't size all the way down leaving the interior ID at the neck-shoulder junction large enough where donut growth doesn't come into play.

I have 2 bushing die from Forster, One for the neck and one full, I think that I made the worst choice of my reloader life...

I think that the best sizing die are the old scool non bushing full length...

Neck sizing with a collet die can squeeze away the donut, moving that brass material into the neck.

You speak for collet sizing by Lee?
I don't think it exists for the 6.5x47 Lapua.
But ok!

The donut can be cut away with a good reamer run through the neck (like the one K&M has).

Choose your poison.

Finishing need some extra work...

Thanks!

 

[straightshooter1]

Yes I can use and expander for the tension of the neck.
Yes I anneal my brass after a single firing.

This is my go to method. I use a Forster FL sizing die that's been reamed so that it only reduces the neck .002 - .003 below my target OD, then use an expander mandrel to set my neck tension. This give me the best neck TIR (they're neck turned after fire forming), and. . . moves any donut away.

FYI: I've tested the ID with pin gauges before sizing to feel the donut and see how thick it is and afterwards to see if the donut is still there.

What angle of cutter I can choice for my 6,5x47 Lapua cases?

A 28° works nicely if you case neck is 30°.

I have 2 bushing die from Forster, One for the neck and one full, I think that I made the worst choice of my reloader life...

I'm just not a fan of bushing dies. Apparently, I have the same two Forster dies and I only use the neck bushing bump die to bump necks whenever I neck size with a collet die.

I think that the best sizing die are the old scool non bushing full length...

As mentioned, that's my preference too.

You speak for collet sizing by Lee?
I don't think it exists for the 6.5x47 Lapua.
But ok!

I think one would have to have Lee do a custom job for that cartridge. And I think there are a couple of other places, more expensive, that can do a custom collet sizing die.

Finishing need some extra work...

Thanks!

I've got a K&M reamer that I got for a test and it did ok. I didn't notice any unusual marks on bullets that I pulled to inspect. I just like the method I've settled on.

 

[JR1200W3]

Best course of action is to prevent it. In your particular case you could have prevented it by paying what Lapua wanted for 6.5x47 brass.

Making Franken brass results in artifacts in the brass like donuts. And now you have to buy tools to try to remedy the artifacts off-setting any real savings from making the Franken brass. The K&m tool is probably the best solution for what you have going on. Wilson also makes an inside neck reamer that will cut out donuts but it requires you to have their trimmer.

 

[RTTY]

Best course of action is to prevent it. In your particular case you could have prevented it by paying what Lapua wanted for 6.5x47 brass.

Can you explain me better please?

Making Franken brass results in artifacts in the brass like donuts. And now you have to buy tools to try to remedy the artifacts off-setting any real savings from making the Franken brass.

What are Franken?
Brand Lapua?
Origin of the brand?
Explain please?

The K&m tool is probably the best solution for what you have going on. Wilson also makes an inside neck reamer that will cut out donuts but it requires you to have their trimmer.

Yes Wilson requiren the brand trimmer.

Thanks

 

[RTTY]

This is my go to method. I use a Forster FL sizing die that's been reamed so that it only reduces the neck .002 - .003 below my target OD, then use an expander mandrel to set my neck tension. This give me the best neck TIR (they're neck turned after fire forming), and. . . moves any donut away.

FYI: I've tested the ID with pin gauges before sizing to feel the donut and see how thick it is and afterwards to see if the donut is still there.

Hooned FL die, ok!

A 28° works nicely if you case neck is 30°.

Perfect!

I'm just not a fan of bushing dies. Apparently, I have the same two Forster dies and I only use the neck bushing bump die to bump necks whenever I neck size with a collet die.


As mentioned, that's my preference too.

Ok!

I think one would have to have Lee do a custom job for that cartridge. And I think there are a couple of other places, more expensive, that can do a custom collet sizing die.

Other brands?

I've got a K&M reamer that I got for a test and it did ok. I didn't notice any unusual marks on bullets that I pulled to inspect. I just like the method I've settled on.

Do you use with an electric drill or battery screwdriver?

Thanks

 

[whatsupdoc]

Couple of points first.
Mandrels never remove doughnuts, pure bullshit.
In my testing I have found the cases that have been resized using a expander ball pulled up through the neck
were less likley to create doughnuts vs pushing a mandrel down into the case. I no longer use mandrels because of this.


Cutting out doughnuts is a pain but there is a way to do it with very good results.

FL resize case (using 6.5 mm)

Push a .264 mandrel (bullet diameter) into the case neck just deep enough into the neck so it stops expanding the
neck just before it contacts the doughnut.

Using a doughnut cutter now will cut out the doughnut without cutting the inside of the neck
because the neck is .001 larger than the cutter.

Resize the case you should be good to go minus the doughnut.

 

[straightshooter1]

Couple of points first.
Mandrels never remove doughnuts, pure bullshit.

You're right, they don't actually "remove" donuts, but the mandrels do essentially move them out of the way, like moving the material to the outside; more so if the cases are annealed.

After annealing (as I do after every firing), I've taken pin gauges to measure the amount of "neck tension" and to see what the ID's of the donuts actually are. I've had as much as .002 difference between the ID of the donut opening and the rest of the case neck. After running my mandrel through the necks then the pin gauges to see any changes in the donut ID, there was no obstruction of the pin gauge all the way through for the "neck tension" I was setting. One of the reasons I bought some pin gauges was to find out definitively the size of the donuts before and after various sizing methods.

For necks that haven't been annealed, particularly those that have never been done after several firings, little or no movement of the donut by running a mandrel through the neck is expected due to the amount of springback.

 

[straightshooter1]

Other brands?

https://portersprecisionproducts.com/product-category/starter-sets/

Do you use with an electric drill or battery screwdriver?

Thanks

I use a cordless drill, same as I use for turning necks.

 

[Baron23]

Best course of action is to prevent it. In your particular case you could have prevented it by paying what Lapua wanted for 6.5x47 brass.

I've my fired cases (6,5x47 Lapua) with donuts.

 

[whatsupdoc]

You're right, they don't actually "remove" donuts, but the mandrels do essentially move them out of the way, like moving the material to the outside; more so if the cases are annealed.

After annealing (as I do after every firing), I've taken pin gauges to measure the amount of "neck tension" and to see what the ID's of the donuts actually are. I've had as much as .002 difference between the ID of the donut opening and the rest of the case neck. After running my mandrel through the necks then the pin gauges to see any changes in the donut ID, there was no obstruction of the pin gauge all the way through for the "neck tension" I was setting. One of the reasons I bought some pin gauges was to find out definitively the size of the donuts before and after various sizing methods.

For necks that haven't been annealed, particularly those that have never been done after several firings, little or no movement of the donut by running a mandrel through the neck is expected due to the amount of springback.

They never move them to the outside that is a farce.

 

[straightshooter1]

They never move them to the outside that is a farce.

OK, if you say so.

 

[JR1200W3]

View attachment 8558990

He made a thread a month ago about forming his own 6.5X47L brass bc Lapua brass is really expensive in his part of the world. Granted, I am making the assumption this is his homemade formed brass and not actual factory brass, but you don't really get donuts randomly in factory brass. You get them when forming brass because former shoulder material becomes neck or similar situations.

I think most of the people here aren't aware of the backstory. Now reread my post and think about forming 6.5x47L brass from 6.5 Creedmoor brass and see if what I said makes any sense.

 

[Baron23]

He made a thread a month ago about forming his own 6.5X47L brass bc Lapua brass is really expensive in his part of the world. Granted, I am making the assumption this is his homemade formed brass and not actual factory brass, but you don't really get donuts randomly in factory brass. You get them when forming brass because former shoulder material becomes neck or similar situations.

I think most of the people here aren't aware of the backstory. Now reread my post and think about forming 6.5x47L brass from 6.5 Creedmoor brass and see if what I said makes any sense.

Yep, with that backstory it makes sense but the OP said it was Lapua cases. Who knows

 

[JR1200W3]

Yep, with that backstory it makes sense but the OP said it was Lapua cases. Who knows

He said "6.5x47 Lapua cases". In a way that Lapua could be a descriptor of the cartridge design more than the Brand of the brass

Also this

Post in thread 'Neck/chamber clearance' https://www.snipershide.com/shooting/threads/neck-chamber-clearance.7238250/post-11875041

 

[Baron23]

He said "6.5x47 Lapua cases". In a way that Lapua could be a descriptor of the cartridge design more than the Brand of the brass

Also this

Post in thread 'Neck/chamber clearance' https://www.snipershide.com/shooting/threads/neck-chamber-clearance.7238250/post-11875041

Ah, now I understand where you’re coming from.

 

[RTTY]

He made a thread a month ago about forming his own 6.5X47L brass bc Lapua brass is really expensive in his part of the world. Granted, I am making the assumption this is his homemade formed brass and not actual factory brass, but you don't really get donuts randomly in factory brass. You get them when forming brass because former shoulder material becomes neck or similar situations.

I think most of the people here aren't aware of the backstory. Now reread my post and think about forming 6.5x47L brass from 6.5 Creedmoor brass and see if what I said makes any sense.

Hello, no the case with donuts are brand Lapua cases, 6,5x47 factory made.

 

[JR1200W3]

Hello, no the case with donuts are brand Lapua cases, 6,5x47 factory made.

Then it's extremely strange that you are getting donuts from factory brass. What are you doing that's creating donuts in the necks? Or are you positive you have donuts in the necks? This doesn't just randomly occur.

 

[RTTY]

Then it's extremely strange that you are getting donuts from factory brass. What are you doing that's creating donuts in the necks? Or are you positive you have donuts in the necks? This doesn't just randomly occur.

Hello, sorry for my bad english and for the mistake, the donuts was formed on the fired factory 6,5x47 Lapua, not brand new.

 

[JR1200W3]

Hello, sorry for my bad english and for the mistake, the donuts was formed on the fired factory 6,5x47 Lapua, not brand new.

You already said that. And then didn't answer the questions.

Whatever, ain't no one got time to figure out how you managed to form donuts in factory brass....

 

[RTTY]

Hello,
the donuts was formed with normal use, normal charges with 35 or 36gn of N150 behind Scenar 139gn. Forming done with Forster bushing neck die and redding body die.