getting rid of the donut?

[pinzmann]

My first experience with the inside donut. I shoot 284 winchester and use Lapua brass which I have to neck up with an expander. Well, after several reloads I noticed a bump when seating the bullets. Looking inside I saw a ridge at the bottom of the neck which I assumed is the donut. Read up some info on this so I got an inside reamer and a neck turning tool. First I tried the reamer on a fired case. No go, too loose. So I resized the cases and tried again. Tight fit but it removed the donut. Then I cleaned up the outside neck mainly because it seemed the was a slight bulge at the shoulder - neck junction. So I went to reload and the bullets just fall in the case. Since I was using a Redding bushing die, I went down one size bushing and it still wont resize the neck enough. And ofcourse I don't have any smaller bushings.
What did I do wrong? I really don't want to use smaller bushings because it seems like I working the neck a lot. Was there a better way to do this?
Even if I was to use smaller size bushings, nobody has them in stock.

 

[fdshuster]

Yes, the formation of donuts is a problem. I first tried a carbide cutting tool claimed to cut them out. Would not work on my 6ppc and 6BR Lapua brass. Cutter diameter was too small to remove the donuts. Then had 2 custom made reamers made by Forster to fit my Forster case trimmer, in addition to already having 2 other sizes. 4 reamers total, and they are either too small or too large. Too small and they will not remove the donut, too large & they would be removing material from the inside of the case necks.

Then tried using 1/4 round jewelers needle files to cut them out. It works, but very time consuming. My way of dealing with them now is to spec my chambering reamers so the bullets seat to touch the lands with the full diameter base at least .020" in front of the donut. Had one chamber that had too short of a freebore and had my gunsmith lengthen it with a throating reamer. End of problem.

Seating the bullets in front of the donuts lets me forget about them.

 

[searcher]

As fdshuster explained - far better to work around the doughnut if you can. As sometimes the doughnut can grow forward towards the case mouth just enough to cause a problem at the base of the bullet contact, I reduce the effect of the doughnut by first annealing the neck, then inside sizing with the neck turning expander, then turn the necks again. You will get the correct amount of metal off when the cutter engages about 2/3 back from the case mouth towards the shoulder. This will not completely make the necks perfect all the way back into the case - but it will alleviate the buildup that is affecting your bullet tension variation, provided you are doing as fdshuster explained above - seating a bullet ahead of the doughnut. I have also found that when using a fair variety of boattail bulets, in conjunction with jamming if that is the load that works in your rifle - it will often put your bullet base ahead of the doughnut problem area until it is time to re-turn the necks again. When turning the neck, be sure to make a slight cut into the shoulder. This will buy you a little more time before having to repeat the process. How often you will need to repeat depends upon your load. I get 5 from one caliber and 12-15 from another. You will notice a big difference AFTER you have fired these cases again to blow the neck area out where the doughnut "used to" reside. I would think having the PERFECT reamer would be ideal - but this method works pretty good for me.

 

[Keith Glasscock]

Or, just adjust your sizing die bushing to only size the upper part of the neck. One really good 284 shooter I know only resizes ~.150" of the neck.

 

[DennisH]

Or, just adjust your sizing die bushing to only size the upper part of the neck. One really good 284 shooter I know only resizes ~.150" of the neck.

I only use 1/2 of the neck as well on my 284.

Dennis

 

[jcampbellsmith]

Try one of these - http://www.sinclairintl.com/reloading-equipment/case-preparation/case-neck-reamers/wilson-neck-reamer-prod33313.aspx Regards JCS

 

[fdshuster]

JCS: Donuts come in a variety of sizes, some are just barely a "bump", others are thicker, and others still are very thick. A wide dimensional difference and to cover all the variables, a wide selection of properly sized reamers would be required. I have over $100 invested in reamers just for 6mm ( 2 off the shelf & 2 custom made), and they are worthless.

 

[338 Mollett]

Dennis that's not a bad idea I can see how that would help center your case in the chamber and the bullet to the bore .

 

[ronemus]

I use an expander to move the donut from the inside to the outside of the neck, then neck-turn to remove it. By the time the donut appears, the neck can use a cleanup anyway. Be sure to turn a bit into the shoulder so the donut takes longer to form.

 

[pdog2225]

I too have run into the donut problem. I shoot a 26AI and have a bunch of new .243 Norma brass. So I turned the necks to even them up and cut into the shoulder. Thinking I now had some great brass. Upon firing them a new bullet would stop at the donut. Tried the K&M carbide cutter, it took off a little but the donut was still there. My solution was labor intensive. I tried different size drill bits until I found one that fit ok but still had enough room in the neck to angle the side of the bit to touch the donut. I put the bit in a T-handle like the kind used for taps. By applying pressure on the neck/shoulder of the case and being careful to not take to much from the inside of the case mouth I was able to remove the donut. Now after two firings there is still no donut. I thought these cases were worth the effort was my reason for doing it. Now I don't use .243 cases for the 260/260AI. pdog2225

 

[fdshuster]

pdog2225: "Tried the K&M carbide cutter, it took off a little but the donut was still there".

My experiences exactly ! And ditto that for the reamers also. Very frustrating. And yes, when outside neck turning I do go into the shoulder.

I now seat the bullets in front of the donuts and "fagedaboudit".

 

[Milo 2.0]

pdog2225: "Tried the K&M carbide cutter, it took off a little but the donut was still there".

My experiences exactly ! And ditto that for the reamers also. Very frustrating. And yes, when outside neck turning I do go into the shoulder.

I now seat the bullets in front of the donuts and "fagedaboudit".

I bought the K&M inside reamer also, it got most of the donut. Their website says you need to buy their "Flatiron" expander system or it will not work. Only stands to reason if you expand the whole neck, the reamer wont cut it out. So it was my fault by not buying their expander.

My only complaint is why can't one company sell the whole package??? I guess K&M does, but I needed the 21st Century lathe, I guess.

 

[amlevin]

Partial neck size and "what donut"?

 

[jcampbellsmith]

JCS: Donuts come in a variety of sizes, some are just barely a "bump", others are thicker, and others still are very thick. A wide dimensional difference and to cover all the variables, a wide selection of properly sized reamers would be required. I have over $100 invested in reamers just for 6mm ( 2 off the shelf & 2 custom made), and they are worthless.

I don't have a lot of experience in these matters, but I have noted doughnuts in my 260 Rem and 243 AI. The Wilson approach worked for me in both these calibres. I just took the fired cases and ran the reamer in at the start of my case prep cycle. I plan to do the same with a crop of 6xc doughnuts that I've got soon.

The odd thing with the 260 Rem was that the neck turned Remington brass never displayed doughnuts, even after 8 or 9 firings. The Nosler brass used without neck turning started showing doughnuts after the fifth firing. Any comments?

Regards

JCS

 

[jlow]

If you have to seat deep enough to have to get rid of the donut, size your brass first with a Lee Collet die to externalize the donut, then trim it off with a neck turner.

 

[Lapua40X]

What did I do wrong? I really don't want to use smaller bushings because it seems like I working the neck a lot. Was there a better way to do this?
Even if I was to use smaller size bushings, nobody has them in stock.

Getting down to your specific question, you reamed the inside of the neck, then turned the outside of the neck. Assuming you used a reamer that matches the caliber of the bullet you were loading, the reamer probably reduced the wall thickness of your neck enough to leave a neck opening large enough to allow the bullet to drop into the case without resistance at that point in the process. Turning the outside of the neck further reduced the neck thickness so the bushing had nothing (or at least not enough) to compress and the neck opening remained too large.
Without a tighter neck sizing bushing there is nothing you can do to correct the problem.
I have a few of those ooops cases resting in a bowl on my reloading bench and and consequently waiting for those "back order" notices from the supplier to disappear so I can order the smaller bushing I need. :'(

 

[BradY]

One method or the other would be the best way to do it, not both. Either just use the inside reamer, or just outside turn. Remember if your going to outside turn you will want to expand with a mandrel- K&M expanders suit K&M turners. Then turn, then neck back down. Take plenty of measurements before and after so you can neck down and have the correct tension on the bullet. In your case this time get some bushings a few thou smaller not just one or two. Your cases might actually be ok to use, just need a smaller bushing.

My shehane chamber is a 318nk (no turn) but I have an inside reamer ready to do its work. Loaded virgin rounds are 313 and I run a 311 bushing which should work out perfect once I inside ream the neck for 1-2 thou tension.

 

[amlevin]

I have a few of those ooops cases resting in a bowl on my reloading bench and and consequently waiting for those "back order" notices from the supplier to disappear so I can order the smaller bushing I need. :'(

I just bought a relatively inexpensive Lee Collet die, sized those cases, and just shot them.

 

[artbosco]

My first experience with the inside donut. I shoot 284 winchester and use Lapua brass which I have to neck up with an expander. Well, after several reloads I noticed a bump when seating the bullets. Looking inside I saw a ridge at the bottom of the neck which I assumed is the donut. Read up some info on this so I got an inside reamer and a neck turning tool. First I tried the reamer on a fired case. No go, too loose. So I resized the cases and tried again. Tight fit but it removed the donut. Then I cleaned up the outside neck mainly because it seemed the was a slight bulge at the shoulder - neck junction. So I went to reload and the bullets just fall in the case. Since I was using a Redding bushing die, I went down one size bushing and it still wont resize the neck enough. And ofcourse I don't have any smaller bushings.
What did I do wrong? I really don't want to use smaller bushings because it seems like I working the neck a lot. Was there a better way to do this?
Even if I was to use smaller size bushings, nobody has them in stock.

Unless you have to seat your bullets below the donut don't worry about them. The 6PPC is shot that way by most with no noted difference on target.

 

[lrgoodger]

I just bought a relatively inexpensive Lee Collet die, sized those cases, and just shot them.

I wish I could FIND a Lee Collet die for the 284 Shehane! Or for a 30BR. Been trying to figure out if I can take a stock 308 collet die and make a 30BR out of it, but I don't think so.