How to create a heat sink to keep neck turning tools cool and precise

[P1ZombieKiller]

1 possible reason for this might be that once brass is fired, it's very hard (not impossible) to get the entire neck small enough to fit perfectly on your turning mandrel.
If not perfectly on your turning mandrel, and loose, the brass "slops" around (think wobbles), thus causing your cutter to cut more brass in other places that it didn't cut into before.


For me and my set up, I won't turn fired brass because once it's fired (and expanded) i can't reduce the whole neck down to my turning mandrel size.

 

[Straightshooter1]

When I turned my cases a 2nd. time the brass removal was everywhere. Not just the donut area. I'll turn a case that was already turned and see if I can put up a pix. I suggest that all of you run your turner a second time and see what happens instead of all of the quesswork replies.

Before you turned your necks for the second time, did you measure their thickness before and after?

Anyway. . . OK, ok, you talked me into doing it, but just on one case. I was hesitant because I really didn't want to have to expand the necks to less "neck tension" to do the turning.

I grabbed a case from that bunch of .308 cases that I turned to .014" which I mentioned before, you know. . . those that have been fired 15 times. After expanding the neck and run the neck into my neck turner, which has been set for .014" neck thickness for a long time, as this is what I always turn my new batches to. As the neck went into the cutter, I there wasn't any noticeable contact until well past half way. Then I saw a couple very fine shards that came off just before I got down to the donut area (I thought they might show up in the picture I took below, but I can't see them). In the picture you can see there is some cuttings from that donut area and into the shoulder.


After this turning, I measured the thickness again, and it's right at that .014 - .0141. Granted, the micrometer I have is not a top tier tool that'd be good for good machining work, but it does the job well enough for what we do. IMHO

 

[JMayo]

I just re turned all my custom 30br cases . They had gone from 10 to 10.25+.
They have been shot 100's of times.
Prolly gonna start new ones soon !

 

[Webster]

Before you turned your necks for the second time, did you measure their thickness before and after?

Anyway. . . OK, ok, you talked me into doing it, but just on one case. I was hesitant because I really didn't want to have to expand the necks to less "neck tension" to do the turning.

I grabbed a case from that bunch of .308 cases that I turned to .014" which I mentioned before, you know. . . those that have been fired 15 times. After expanding the neck and run the neck into my neck turner, which has been set for .014" neck thickness for a long time, as this is what I always turn my new batches to. As the neck went into the cutter, I there wasn't any noticeable contact until well past half way. Then I saw a couple very fine shards that came off just before I got down to the donut area (I thought they might show up in the picture I took below, but I can't see them). In the picture you can see there is some cuttings from that donut area and into the shoulder.
View attachment 1615141

After this turning, I measured the thickness again, and it's right at that .014 - .0141. Granted, the micrometer I have is not a top tier tool that'd be good for good machining work, but it does the job well enough for what we do. IMHO
View attachment 1615142

I'll bet the chips you removed were close to 2 thou thick.

Just did a quick 2nd neck turn on 3 6BRX cases. They were originally turned to .0125” and fired about 5 times. I measured the necks with a ball mic by the mouth, mid-length and near the shoulder. They measured about 0.0115” near the mouth, about 0.0125” mid length and 0.0131” by the shoulder. Ran the expander mandrel in each case then ran the turner on each neck. The cases were not bright and shiny so it was easy to see where the cutting occurred. I got the same results you got. The cutting started about mid-length up to the shoulder. Not much sense turning to within 0.0001” if the dimensions change after 1 shot. Sounds to me there are more important things to worry about unless you want to compete at national matches. I never got real serious reading wind since all I needed was to hit a GH at 350 yards.

 

[Straightshooter1]

I just re turned all my custom 30br cases . They had gone from 10 to 10.25+.
They have been shot 100's of times.
Prolly gonna start new ones soon !

Makes me wonder if some caliber/cases are more susceptible to this kind of neck thickness growth??? I just don't see in my Lapua .308 cases. And/or there's something different in the case prep. . . like more case case body reduction when sized???

 

[Webster]

From what I read shooting pushes shoulder brass forward creating the donut in the neck, sizing pushes downward on the brass. Whatever I am not worried about it. My guns are good enough for me without getting anal about reloading. No matter what the subject is there is always someone that says if I do this I see an improvement. I only pay attension to what the top short range bench shooters do. And I cannot do or afford what they do.

 

[WyleWD]

K&M has the ergo holder

View attachment 1613962

https://kmshooting.com/product/ergo-holder/

One of the best additions to the K&M that I use. Serves as a heat sink and WAY more comfortable than holding the cutter itself. JME.WD

 

[ebb]

With the number of variables that exist within the amount of time it takes to shoot a rifle match, how could you possibly say with any certainty X count went up because of neck turning changes? Over the day of the match 2 more or 2 less gusts of wind may have had more impact. 3 more sips of coffee, maybe todays blood pressure pill was .2 milligrams stronger than last matches pill, maybe you farted one more time one the bench and made 2 better shots. maybe the sun was at a different angle and you had glare, what if the magnetic poles changed a little that day. I am not trying to be an ass, I am trying to understand. Does any of this minutia matter? Yes I am sure some of it does to some extent. But with all the MILLIONS of variables that exist in the real world how can you be sure what matters and what doesn't? I seldom get to shoot at enough distance to actually have an opinion, so maybe I am totally wrong, but wind seems to be 100 levels of magnitude more important than of this stuff. I want so much to be proven wrong, and I can sort primers and turn necks better and be a national champion, then the frisky runway models will love me. When I was shooting at manatee i looked at my ballistic charts, the 338LAP the 300RUM the 7RUM the 6.5-284from a 100yd zero all of them were about 94 -96 clicks and within 4 clicks of each other to get on at 1000yds. It seemed as all of my searching for a better cartridge was a waste of time. Maybe the phrase is right, maybe its the Indian not the arrow.

 

[Webster]

1 possible reason for this might be that once brass is fired, it's very hard (not impossible) to get the entire neck small enough to fit perfectly on your turning mandrel.
If not perfectly on your turning mandrel, and loose, the brass "slops" around (think wobbles), thus causing your cutter to cut more brass in other places that it didn't cut into before.


For me and my set up, I won't turn fired brass because once it's fired (and expanded) i can't reduce the whole neck down to my turning mandrel size.

Don't understand, you can make the neck diameter any dimension you want.

 

[P1ZombieKiller]

With the number of variables that exist within the amount of time it takes to shoot a rifle match, how could you possibly say with any certainty X count went up because of neck turning changes? Over the day of the match 2 more or 2 less gusts of wind may have had more impact. 3 more sips of coffee, maybe todays blood pressure pill was .2 milligrams stronger than last matches pill, maybe you farted one more time one the bench and made 2 better shots. maybe the sun was at a different angle and you had glare, what if the magnetic poles changed a little that day. I am not trying to be an ass, I am trying to understand. Does any of this minutia matter? Yes I am sure some of it does to some extent. But with all the MILLIONS of variables that exist in the real world how can you be sure what matters and what doesn't? I seldom get to shoot at enough distance to actually have an opinion, so maybe I am totally wrong, but wind seems to be 100 levels of magnitude more important than of this stuff. I want so much to be proven wrong, and I can sort primers and turn necks better and be a national champion, then the frisky runway models will love me. When I was shooting at manatee i looked at my ballistic charts, the 338LAP the 300RUM the 7RUM the 6.5-284from a 100yd zero all of them were about 94 -96 clicks and within 4 clicks of each other to get on at 1000yds. It seemed as all of my searching for a better cartridge was a waste of time. Maybe the phrase is right, maybe its the Indian not the arrow.

I have shot 100 VFS at our club for 7 straight years (excluding 2020). Our 100 yard range has concrete walls down both sides of the range. The wind is (for the most part) constant.

My average X count on the rifle barrel i concluded this and changed the neck tension on was 19.2, 19.7, and 19.5 for 3 straight years. The last year i shot that barrel the only thing I changed was the neck tension. My x count was 21.3 once I changed the neck tension.

I feel that was enough evidence for me to conclude it was the neck tension.

Hopefully that answered your question..

 

[P1ZombieKiller]

Don't understand, you can make the neck diameter any dimension you want.

Yes You can. But in order for the neck to slide on the mandrel perfectly, it has to be the correct diameter.... not demension.

I am going to use made up exaggerated numbers because I don't actually know the real numbers.

if you size the virgin 6br brass to .307, and it slides onto the turning mandrel perfectly, you know 307 is where it needs to be.

But if you fired the brass and it expanded to .310, it is difficult (not impossible) to size that entire brass neck back down to .307 to where it fits your mandrel perfectly.

If you dont size the whole neck back down, and slide that .310 brass over your .307 mandrel, it fits too loose and the cut will be sloppy.

I am not good with words, but I have been making 30br brass for 15 years now and have learned alot. I most certianly don't know it all, and apologize if I sound like I do. I just know that 75,000 pieces of 30 br brass and I have only had 4 customers want to send it back, 2 of which i most certianly made the mistake.

There are alot of people on this forum (like @jackieschmidt ) that turn after fireforming and are exceptional shooters. And that pricess works for them. I just don't know their process and don't know what they go through in order for it to work for them.

 

[JFrank]

I have shot 100 VFS at our club for 7 straight years (excluding 2020). Our 100 yard range has concrete walls down both sides of the range. The wind is (for the most part) constant.

My average X count on the rifle barrel i concluded this and changed the neck tension on was 19.2, 19.7, and 19.5 for 3 straight years. The last year i shot that barrel the only thing I changed was the neck tension. My x count was 21.3 once I changed the neck tension.

I feel that was enough evidence for me to conclude it was the neck tension.

Hopefully that answered your question..

We seem to be wandering off topic a bit ( my apologies to the OP) but to follow up a thought.

I could easily understand your X count going up after tuning the amount of bullet hold applied, I see definite improvements in group consistency when I test and get on the right bushing.
Although using my current style of testing I find it difficult to judge improvements or decline at short range vs a greater distance that adds separation.

 

[P1ZombieKiller]

We seem to be wandering off topic a bit ( my apologies to the OP) but to follow up a thought.

I could easily understand your X count going up after tuning the amount of bullet hold applied, I see definite improvements in group consistency when I test and get on the right bushing.
Although using my current style of testing I find it difficult to judge improvements or decline at short range vs a greater distance that adds separation.

is that because you shoot long range?
I shoot short range and the 30br (imho) is not a 300+ yard caliber.
The bullet I shoot is a 108 grain 308 caliber flat base bullet. It will not have the performance at 500 yards a 200 grain boat tail will.

 

[JFrank]

Is that because you shoot long range?

Could be partly bullet type or perhaps the caliber. As I mentioned I could understand X count improvement with the correct bushing.

 

[Webster]

Yes You can. But in order for the neck to slide on the mandrel perfectly, it has to be the correct diameter.... not demension.

I am going to use made up exaggerated numbers because I don't actually know the real numbers.

if you size the virgin 6br brass to .307, and it slides onto the turning mandrel perfectly, you know 307 is where it needs to be.

But if you fired the brass and it expanded to .310, it is difficult (not impossible) to size that entire brass neck back down to .307 to where it fits your mandrel perfectly.

If you dont size the whole neck back down, and slide that .310 brass over your .307 mandrel, it fits too loose and the cut will be sloppy.

I am not good with words, but I have been making 30br brass for 15 years now and have learned alot. I most certianly don't know it all, and apologize if I sound like I do. I just know that 75,000 pieces of 30 br brass and I have only had 4 customers want to send it back, 2 of which i most certianly made the mistake.

There are alot of people on this forum (like @jackieschmidt ) that turn after fireforming and are exceptional shooters. And that pricess works for them. I just don't know their process and don't know what they go through in order for it to work for them.

Reread your post. I think what you are saying is a FL bushing die only sizes half the length of the neck making the turning cutter mandrel only fit well in the first half of the neck. That assumes the neck turning expander mandrel doesn't touch the back half of the neck. Someone else can figure this out. I believe a lot of the top long range shooters use bushing dies. Are they using standard FL dies that don't have bushings to size the entire neck before turning? Need to review the Jack Neary video on case prep.