removing doughnut ring

[cognac jack]

I am new to long range shooting and cannot understand how to remove the doughnut after the first firing of new brass that had the neck turned. Where I get lost is how do you size the neck so you are only cutting the doughnut and not taking any material away from the inside of the rest of the neck.Any help would be appreciated.

 

[Terry]

If you run a mandrel or expander through the case the donut will move to the outside where you can neck turn it off.

Terry

 

[NorCalMikie]

What Terry said. And, if the doghnut forms in the "inside", is the seated bullet going to contact that area? You might consider leaving it alone?

 

[mshelton]

Make sure that the cutter on your neck turner is angled to match the case shoulder, then when turning to remove the doughnut just ever so lightly touch the shoulder to blend the neck and shoulder brass together.

 

[cognac jack]

thanks everyone, I was trying to cut it from the inside, this will make it a lot easier

 

[AlNyhus]

cognac jack: The first step to fixing donuts in a fired case is to.....don't size anything!. Not the case body, not any part of the neck.....don't touch anything!

This way, all the donut is inside the case neck and can easily be dealt with, given the proper setup. Anything you do as far as sizing, etc. to a fired case will not only limit your success with dealing woth the donut but can give you accuracy woes that are very subtle and hard to find.

Good shootin'. -Al

 

[turbo54]

cognac jack: The first step to fixing donuts in a fired case is to.....don't size anything!. Not the case body, not any part of the neck.....don't touch anything!

This way, all the donut is inside the case neck and can easily be dealt with, given the proper setup. Anything you do as far as sizing, etc. to a fired case will not only limit your success with dealing woth the donut but can give you accuracy woes that are very subtle and hard to find.

Good shootin'. -Al

Your post is rather vague in regard to actually dealing with the donut.

Are you suggesting throwing the brass away when a donut forms?

What is your magic easy way to deal with the donut?

 

[AlNyhus]

Your post is rather vague in regard to actually dealing with the donut.
-That's because the best way to deal with it, is when the case in it it's fired form.

Are you suggesting throwing the brass away when a donut forms?
Where did you get that from anyting I posted?

What is your magic easy way to deal with the donut?[/quote]
I don't see the words "magic" or "easy" in anything I posted, either.

Good shootin'. -Al

 

[TimP]

I had a doughnut form in some .243 Win brass. I purchased an inside neck reamer for my Wilson trimer and it removed the doughnut with a couple of quick turns. Do not size the cases in any way or form prior to using the reamer.

 

[treeman]

the way I deal with donuts is to measure the inside diameter of the neck and get a chucking reamer that size and use a slow speed drill and ream out the donut. purpose made inside neck reamers are not always the right size. chucking reamers cane be had in any size

 

[cognac jack]

well I thought I knew how to do it but now I am even more confused, K&M makes an inside reamer, it sounds like you are supposed to ream the doughnut with that reamer. Are you supposed to do it with a fired case that has not been touched. Does the K&M reamer match the size of the fired shell, by the way I am doing all this on a 6.5x284 lapua cartridge.

 

[turbo54]

[quote author=AlNyhus]
Your post is rather vague in regard to actually dealing with the donut.
-That's because the best way to deal with it, is when the case in it it's fired form.

Are you suggesting throwing the brass away when a donut forms?
Where did you get that from anyting I posted?

What is your magic easy way to deal with the donut?
I don't see the words "magic" or "easy" in anything I posted, either.

Good shootin'. -Al
[/quote]

Wow, very helpful.

Thank you for your award winning contribution.

 

[AlNyhus]

Wow, very helpful.
Thank you for your award winning contribution.

turbo54: I tend to not waste my time on responses that are condescending.

With that out of the way, my experience is that the best way to deal with donuts is when the case is in the fired form. The neck o.d. is as perfect and straight as it will ever be...and any donut will be inside the case neck. The trick is to remove as much of the donut as feasable while not in any way touching the inside of the neck that doesn't exhibit any part of the donut. If you do, the neck i.d. on the 'z' axis' will not be parallel with the neck o.d. on the long (z) axis. This will cause accuracy grief that is very hard to track down.

As mentioned by others, a chucking reamer can be useful as well as K&M's cutter mandrel. My own approach is to use Wilson cutters ground to specific dimensions. The 'off the shelf' Wilson reamers will run about .003 over bullet diameter.

These pics may illustrate my process a bit better:

I made up this flanged bushing to 'extend' the reamer and offer better support through the guide:

Bushing installed and ready to ream:

Set up properly, you can use a cutter within .001 of the case neck i.d., cut the donut and never so much as disturb the powder resiue in the neck.

Lots of ways to skin a cat..this one works for me (and other competitors whose cases I maintain).

 

[cba257]

Case neck doughnuts are to accurate shooters as best caliber is to elk hunters.

 

[JamesnTN]

I use Wilson trimmers and as mentioned above with Wilson reamers they will custom grind a reamer to your specs what I have done was have my reamers ground about .0003 larger than my bullet dia I'm using and this allows for my best loaded ammo to date when I was shooting600 yard matches all my loaded ammo using a pressure gauge to seat the bullets were within 6 Ozs of one another which in turn made my es low and loaded rnds very consistent.

 

[jonbearman]

Good imfo right here.K&M make cutters for your neck turning with a 30 degree end on it to just kiss the shoulder and make that blend as posted earlier.Just figure out by the cartridge drawing what angle the shoulder is and give them a call.

 

[cognac jack]

thanks everyone I think I got it figured out now,

 

[garyw]

just reading this thread with intrest-will a donut lead to ES in velocity.?

 

[AlNyhus]

Depends.... -Al

 

[turbo54]

just reading this thread with intrest-will a donut lead to ES in velocity.?

Donut won't make a lick of difference if the shank (bearing surface) of the bullet is north of the neck/shoulder junction when seated.

Donut sux donkey nuts and really, really screws you if you seat your bullets deeper.

I run a 284 repeater on a short action, with a COAL of 2.950"...ask me how I know this.