First time annealing now I'm seeing the dreaded donut

[fdshuster]

After reading everyone's way of dealing with the donuts, and all the hassle involved in many ways, I'm even more convinced that seating the bullets so they are not contacting the donut is the easiest way, for me.

If I'm unable to seat without touching the donut, then I'll continue to use the jewelers needle file & cut them out. But that rarely happens.

Luke_NL: I don't believe the donuts all form with the same consistancy. Some will be thicker or thinner than others, so how do you get a procedure or cutting tool that will remove them all? Yes, a reamer might cut some, and playing with different bushings may work, but this problem is one of different donut thicknesses.

That's been proven to me when I've cut them out with the needle file. Identical 20 pieces of Lapua brass, all loaded the same number of times, and a few will have just the slightest trace of a donut, easily & quickly removed with the file, others in that same box of 20 will have a thicker restriction requiring a lot of cutting with the file.

An example of inconsistancies in the brass itself is seen when trimming to length. Out of a box of 20, again all fired the same number of times with the identical load, some will require .005" to .010" trimming to reach the target length, while some will just need a few thousandth's and others will require no trimming at all.

 

[Bob Sebold]

If you do not know a good gunsmith well you might not be able to do this. I do and it works good for me. You need to first gauge the neck of a fired round with pins to find proper size. Then my gunsmith took a hardend bolt he had laying around and precision ground it square to that diameter. Cost to me, nothing. Bought him some beer and helped him drink it! You can gwet them ground to within .0001 inch if you want. It was a peice of cake. You only need thousands of dollars worth of equipment. I hold it an an old handle for turning brass as head of bolt is round. Pulls donut out with no problem.

 

[thefitter]

What a joyfull hobby ;D ;D Seems like every good step we take causes a thorn in the side down da road. Kinda like getting married

Yeah, but I can get up and walk out of my loading room anytime I need to take a break. 8)

 

[lpreddick]

the wilson internal reamer does a great job on donuts and removing the thicker brass at the base of the neck after it's pushed in by the bushing. neck turning will reduce this, but some seems to remain. i'm trying this to see if it helps me...i know almost nobody does this, esp the benchresters. the reamer handle comes off and i cover the threads with a little piece of electrical tape to allow me to "screw" on the handle from the trimmer, THEN replace the reamer knob to hold the handle on tightly and i'm set. the mechanical advantage is wonderful as i can ream donuts all day without cramps i got when using the round reamer handle. i'm trying to decide if uniforming the entire neck gives a more uniform "grip" on a deeply seated bullet. neck turning probably does this, but internal reaming is easier for me to do and i like trying something different all the time...many failures but once in awhile...

 

[VaniB]

For 308 and 223 I size down the fired brass cases, and then use a K&M expandiron to bring the neck back up where it should be. It expands the donut right out. However, some brand cases will not hold the bullet firm enough after the neck was exapnded with the expandiron. So I have to use a Redding bushing on those cases to shrink it down 1 more thousandths. It's a lot of fussing, but it gets rid of the donut.

 

[Old Navy]

Can't stand it any longer. I just have to ask. What problem is either dough nut causing? Later! Frank

 

[Rtheurer]

One of the most important parts of creating acurate consistant ammo.... Consistant Neck Tension. Personally I think its #1 in the whole scheme of things.
RT

 

[Rtheurer]

I ran across this from Larry Medler when I was looking into sizing 22-250 brass into 6mm Swiss match brass. Even if it does not work for you there is alot of good reading on his site.

http://home.comcast.net/~jesse99/6XC_DonutCutter.html


RussT

 

[lpreddick]

i totally agree that neck tension, controlling the pressure level inside a case required to begin bullet release, seems to have a very significant effect on accuracy. i have fired two groups of exact loadings, except half had .001 more "tension" (redding bushing) and they went into two separate groups. i'm also convinced that "neck tension" changes over time and can significantly affect groups and accuracy. a donut doesn't seem to cause a problem UNLESS you seat a bullet thru the thing. i purposely did this with a 6.5-284 and the VERY HARD donut compressed the jacket by .001 in! haven't been able to anneal them out either and once established, i haven't had much luck with a neck expander...the wilson internal reamer cuts them nicely.

 

[fdshuster]

Frank Blum: If bullets are seated so they are making contact with the donuts, they will have different neck tensions. On firing, some bullets will release easily from the case neck, others will be held in place, (while pressure continues to increase). Not good for group sizes/accuracy & if pressures are high enough with the load(s) being used, could be a safety problem.

When seating on top of a donut I can feel the added resistance and I know there is a donut in that particular case. Bullet will seat with normal feel, then at a point when almost fully seated, I can feel additional resistance.

 

[sailhertoo]

i have formed donuts while necking down brass? the brass is being pushed down and if it slightly "telescopes", it has to go somewhere...outside and inside. i have been very successful in reaming donuts using a wilson case holder and a wilson internal neck reamer. the case is held securely and the reamer passes into the neck very straight. a little brass is taken before encountering the donut, depending on which bushing is used to size the neck. you have to twist the reamers by hand and after doing 50 or more, i can get a hand cramp! the handle on the wilson case trimmer will not fit the reamer, which would make this a snap. i'm looking into having a handle welded to the base of a trimmer handle. an established donut is VERY HARD and can take some effort to remove as above and viewing the results with a borescope is interesting.

Could you send us a picture of your set up if its not too much trouble?

Thanks

 

[Old Navy]

I should have phrased the question better. If you are not seating into the internal dough nut all is well? I re-size with a FL bushing die. Can't see/feel an internal dough nut but might be a little one on the outside. Thanks. Frank

 

[fdshuster]

Frank; I don't see a problem with there being an internal donut when the base of the bullet is seated at least a few thousandths forward. I take a measurement (off the ogive) using the intended bullet, record that length, then be sure that my seating depth is longer.

And when I spec a new reamer that's one of the considerations when deciding on freebore length.

For a donut on the outside seems to me that it would be no different than the small raised area we get when sizing using a neck bushing die that does not make contact all the way to the neck/shoulder junction. I'd outside neck turn to get rid of raised area, but then I'd be worried about cutting the brass too thin & have the neck break-off & stick in the chamber. Create a new problem when attempting to fix an old one.