thinking about getting into precision reloading after a 15y absence. neck turning for concentrcity is a thing i am looking at. i am looking for info on the "donut" formed by that. why/how does it form? what to do about it? i have never been able to get my head around the concept or how it happens. also,any input re: outside neck turning vs inside neck reaming and how they might fit into when/how to resize. thanks.
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neck turning and it's issues
- Thread starter mosin46
- Start date
Re: neck turning and it's issues
There are many opinions on why or how donuts arrive. The K&M neck turning pilots are fluted on the tips to remove the donut. They work very well. I neck turn for a few cartridges and use the K&M tool, it works well.
There are many opinions on why or how donuts arrive. The K&M neck turning pilots are fluted on the tips to remove the donut. They work very well. I neck turn for a few cartridges and use the K&M tool, it works well.
Re: neck turning and it's issues
i turn the necks and then after several reloadings when i start to notice the brass is flowing i turn them again
i turn the necks and then after several reloadings when i start to notice the brass is flowing i turn them again
Re: neck turning and it's issues
IMHO inside reaming is not needed with outside turning, the expander mandrel moves the donut to the outside and the turner cuts it off, should a donut reappear simply turn the neck again, I have yet to have one come back on the brass I have turned for my 260, some of my brass has 20 reloads, the donut forms from the firing, the brass is pushed foward in the chamber, the outside expands to the chamber walls, the flow of the brass has to go somewhere, so the interior gets smaller at the base of the neck, hence the donut, over bore rounds(big cases small bullets) make donuts where as a round like a 308 does not form them or not nearly as fast as the over bore rounds.
IMHO inside reaming is not needed with outside turning, the expander mandrel moves the donut to the outside and the turner cuts it off, should a donut reappear simply turn the neck again, I have yet to have one come back on the brass I have turned for my 260, some of my brass has 20 reloads, the donut forms from the firing, the brass is pushed foward in the chamber, the outside expands to the chamber walls, the flow of the brass has to go somewhere, so the interior gets smaller at the base of the neck, hence the donut, over bore rounds(big cases small bullets) make donuts where as a round like a 308 does not form them or not nearly as fast as the over bore rounds.
Re: neck turning and it's issues
To prevent donuts, you need to make sure the blade bites into the shoulder just a little bit. If you don't, then the brass at the neck / shoulder juncture will flow forward as you shoot, creating a donut that moves forward.
A note on the bite into the shoulder... don't bite too much or you will find the neck breaking off at the shoulder when you shoot... been there done that. Also if you turn twice as suggested above, don't bite into the shoulder on the second turning for the same reason.
To prevent donuts, you need to make sure the blade bites into the shoulder just a little bit. If you don't, then the brass at the neck / shoulder juncture will flow forward as you shoot, creating a donut that moves forward.
A note on the bite into the shoulder... don't bite too much or you will find the neck breaking off at the shoulder when you shoot... been there done that. Also if you turn twice as suggested above, don't bite into the shoulder on the second turning for the same reason.
Re: neck turning and it's issues
i've been told you shouldn't inside neck ream for any reason (though i think if your making donuts that would be one reason , or forming brass)
you should only turn your necks if your using a tight neck chamber that requires it.
turning cases for chambers that dont require them typically produces "worse" accuracy, ( according to several tests i did on my little pressure trace machine). I would guess the extra expansion for turned cases is a bad thing, enough to overshadow any coincentric gains
Unless you had the chamber/reamer made to be that tight , chances are you shouldnt be neck turning for that gun.
but if your chamber is tight , I believe its best to turn your cases on the same mandrel you expanded them on and you can get a donut if you don't turn your cases all the way down to the shoulder.
hope that helps
i've been told you shouldn't inside neck ream for any reason (though i think if your making donuts that would be one reason , or forming brass)
you should only turn your necks if your using a tight neck chamber that requires it.
turning cases for chambers that dont require them typically produces "worse" accuracy, ( according to several tests i did on my little pressure trace machine). I would guess the extra expansion for turned cases is a bad thing, enough to overshadow any coincentric gains
Unless you had the chamber/reamer made to be that tight , chances are you shouldnt be neck turning for that gun.
but if your chamber is tight , I believe its best to turn your cases on the same mandrel you expanded them on and you can get a donut if you don't turn your cases all the way down to the shoulder.
hope that helps
Re: neck turning and it's issues
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: MALLARD</div><div class="ubbcode-body">
turning cases for chambers that dont require them typically produces "worse" accuracy, ( according to several tests i did on my little pressure trace machine). I would guess the extra expansion for turned cases is a bad thing, enough to overshadow any coincentric gains
Unless you had the chamber/reamer made to be that tight , chances are you shouldnt be neck turning for that gun.
but if your chamber is tight , I believe its best to turn your cases on the same mandrel you expanded them on and you can get a donut if you don't turn your cases all the way down to the shoulder.
hope that helps</div></div>
Yes and no. It really depends on the neck to chamber clearance. For a factory chamber, that dimension is already roomy, so if you take, say, Winchester brass, which tends to be on the thin side, and you turn that further, then further increasing that neck to chamber clearance will cause more wear on your neck as the neck has to spread open wider to seal the chamber during firing. It might also hinder accuracy to have too much of that dimension.
But then, if you are using Lapua, Norma, Federal, or Lake City Brass, the brass is substantially thicker and you can still skim the outside and be a lot thicker than unturned Winchester brass.
I skim my Lapua brass and my necks stay plenty thick. Plus, I get some benefit in concentricity and neck tension uniformity. I admit that I haven't done enough tests to see the benefit in group size, though I definitely see about a 15% improvement in concentricity and more importantly, I end up with more loaded cartridges that meet my personal "match" spec of < .0015" of runout.
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: MALLARD</div><div class="ubbcode-body">
turning cases for chambers that dont require them typically produces "worse" accuracy, ( according to several tests i did on my little pressure trace machine). I would guess the extra expansion for turned cases is a bad thing, enough to overshadow any coincentric gains
Unless you had the chamber/reamer made to be that tight , chances are you shouldnt be neck turning for that gun.
but if your chamber is tight , I believe its best to turn your cases on the same mandrel you expanded them on and you can get a donut if you don't turn your cases all the way down to the shoulder.
hope that helps</div></div>
Yes and no. It really depends on the neck to chamber clearance. For a factory chamber, that dimension is already roomy, so if you take, say, Winchester brass, which tends to be on the thin side, and you turn that further, then further increasing that neck to chamber clearance will cause more wear on your neck as the neck has to spread open wider to seal the chamber during firing. It might also hinder accuracy to have too much of that dimension.
But then, if you are using Lapua, Norma, Federal, or Lake City Brass, the brass is substantially thicker and you can still skim the outside and be a lot thicker than unturned Winchester brass.
I skim my Lapua brass and my necks stay plenty thick. Plus, I get some benefit in concentricity and neck tension uniformity. I admit that I haven't done enough tests to see the benefit in group size, though I definitely see about a 15% improvement in concentricity and more importantly, I end up with more loaded cartridges that meet my personal "match" spec of < .0015" of runout.
Re: neck turning and it's issues
Carter,
Do you find skimming Lapua brass worth the effort?
I used to, but was never able to see an upside so now just pitch the brass at somewhere between 10-15 firings.
I do anneal every firing.
Carter,
Do you find skimming Lapua brass worth the effort?
I used to, but was never able to see an upside so now just pitch the brass at somewhere between 10-15 firings.
I do anneal every firing.
Re: neck turning and it's issues
It's a good question. I am fine with marginal improvement. I have 300 turned cases, so I don't have to answer the question of whether I would do it again for a while.
Another thing to consider is that not every lot of Lapua brass is the same. My Lapua Palma cases, ironically, showed a lot of variation, so I skimmed. I have had lots that haven't varied as much.
In the future, I will spot check the brass. If I don't like the uniformity, I will skim. If I do... I might not.
It's a good question. I am fine with marginal improvement. I have 300 turned cases, so I don't have to answer the question of whether I would do it again for a while.
Another thing to consider is that not every lot of Lapua brass is the same. My Lapua Palma cases, ironically, showed a lot of variation, so I skimmed. I have had lots that haven't varied as much.
In the future, I will spot check the brass. If I don't like the uniformity, I will skim. If I do... I might not.
Re: neck turning and it's issues
Good points.
I usually buy brass is abnormally large lots so as to get as much consistency as is possible. After hearing others complain I realize I must be lucky with my Lapua purchases.
That said you are right, differing thickness results in differing neck tensions and decreased accuracy.
Do you anneal every firing?
I do.
Peace
Good points.
I usually buy brass is abnormally large lots so as to get as much consistency as is possible. After hearing others complain I realize I must be lucky with my Lapua purchases.
That said you are right, differing thickness results in differing neck tensions and decreased accuracy.
Do you anneal every firing?
I do.
Peace
Re: neck turning and it's issues
I think Mallard gives good advice. If you have a factory chamber, you can outside turn the necks maybe 50% or so just to feel good, but otherwise, unless you have a spec'ed tight neck and know what it is and have straight line seating dies or possibly Redding bushing dies, I think neck turning and worrying about donuts is counterproductive. BB
I think Mallard gives good advice. If you have a factory chamber, you can outside turn the necks maybe 50% or so just to feel good, but otherwise, unless you have a spec'ed tight neck and know what it is and have straight line seating dies or possibly Redding bushing dies, I think neck turning and worrying about donuts is counterproductive. BB
Re: neck turning and it's issues
Yes, I anneal every firing. I do lots of crazy things because I am anal. I don't mind turning necks because it is done one (or twice) in the life of the case, which for me is 15 or more firings. In the big scheme of things, the time ends up being not that big of a deal.
Yes, I anneal every firing. I do lots of crazy things because I am anal. I don't mind turning necks because it is done one (or twice) in the life of the case, which for me is 15 or more firings. In the big scheme of things, the time ends up being not that big of a deal.
Re: neck turning and it's issues
<div class="ubbcode-block"><div class="ubbcode-header">Quote:</div><div class="ubbcode-body">I do lots of crazy things because I am anal. </div></div>
LOL... Carter at least you are honest. I do lots of them too, I'm just not as quick to put it out there on the forum. I learned this year that turning once is not enough, depending upon how long the brass lasts. I had to give my F-Class 7WSM brass a second turning earlier this year. Its got roughly 12 firings under its belt at this point.
I anneal every other firing. I must be slacking off...
Jeffvn
<div class="ubbcode-block"><div class="ubbcode-header">Quote:</div><div class="ubbcode-body">I do lots of crazy things because I am anal. </div></div>
LOL... Carter at least you are honest. I do lots of them too, I'm just not as quick to put it out there on the forum. I learned this year that turning once is not enough, depending upon how long the brass lasts. I had to give my F-Class 7WSM brass a second turning earlier this year. Its got roughly 12 firings under its belt at this point.
I anneal every other firing. I must be slacking off...
Jeffvn
Re: neck turning and it's issues
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Jeffvn</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Quote:</div><div class="ubbcode-body">I do lots of crazy things because I am anal. </div></div>
LOL... Carter at least you are honest. I do lots of them too, I'm just not as quick to put it out there on the forum. I learned this year that turning once is not enough, depending upon how long the brass lasts. I had to give my F-Class 7WSM brass a second turning earlier this year. Its got roughly 12 firings under its belt at this point.
I anneal every other firing. I must be slacking off...
Jeffvn </div></div>
I'm raising my hands as a fellow AA member "Anal Accuracy",LOL.
I've turned my necks twice now but only took off .0005 the second time. Did you guys by chance notice that some of the necks were still a little uneven? I could see where part of the neck was shiny and part was still tarnished. The difference is barely measurable.
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Jeffvn</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Quote:</div><div class="ubbcode-body">I do lots of crazy things because I am anal. </div></div>
LOL... Carter at least you are honest. I do lots of them too, I'm just not as quick to put it out there on the forum. I learned this year that turning once is not enough, depending upon how long the brass lasts. I had to give my F-Class 7WSM brass a second turning earlier this year. Its got roughly 12 firings under its belt at this point.
I anneal every other firing. I must be slacking off...
Jeffvn </div></div>
I'm raising my hands as a fellow AA member "Anal Accuracy",LOL.
I've turned my necks twice now but only took off .0005 the second time. Did you guys by chance notice that some of the necks were still a little uneven? I could see where part of the neck was shiny and part was still tarnished. The difference is barely measurable.
Re: neck turning and it's issues
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: MALLARD</div><div class="ubbcode-body">i've been told you shouldn't inside neck ream for any reason (though i think if your making donuts that would be one reason , or forming brass)
you should only turn your necks if your using a tight neck chamber that requires it.
turning cases for chambers that dont require them typically produces "worse" accuracy, ( according to several tests i did on my little pressure trace machine). I would guess the extra expansion for turned cases is a bad thing, enough to overshadow any coincentric gains
Unless you had the chamber/reamer made to be that tight , chances are you shouldnt be neck turning for that gun.
but if your chamber is tight , I believe its best to turn your cases on the same mandrel you expanded them on and you can get a donut if you don't turn your cases all the way down to the shoulder.
hope that helps </div></div>
I think in general you are correct. However...
I had a 243WSSM once. The brass consistency was horrible in nearly every aspect! The rifle reflected this. The worse pieces had 2.5 thou difference from one side of the neck to the other. Neck turning changed a 2.75 MOA gun to a 1.5 MOA gun. Of course it then caused to much neck expansion, thus a split neck here and there. At least I didn't feel I was shooting a shotgun anymore
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: MALLARD</div><div class="ubbcode-body">i've been told you shouldn't inside neck ream for any reason (though i think if your making donuts that would be one reason , or forming brass)
you should only turn your necks if your using a tight neck chamber that requires it.
turning cases for chambers that dont require them typically produces "worse" accuracy, ( according to several tests i did on my little pressure trace machine). I would guess the extra expansion for turned cases is a bad thing, enough to overshadow any coincentric gains
Unless you had the chamber/reamer made to be that tight , chances are you shouldnt be neck turning for that gun.
but if your chamber is tight , I believe its best to turn your cases on the same mandrel you expanded them on and you can get a donut if you don't turn your cases all the way down to the shoulder.
hope that helps </div></div>
I think in general you are correct. However...
I had a 243WSSM once. The brass consistency was horrible in nearly every aspect! The rifle reflected this. The worse pieces had 2.5 thou difference from one side of the neck to the other. Neck turning changed a 2.75 MOA gun to a 1.5 MOA gun. Of course it then caused to much neck expansion, thus a split neck here and there. At least I didn't feel I was shooting a shotgun anymore
Re: neck turning and it's issues
I bought one of those Bench Source annealing machines.
A little tempilac followed by some quick setup made annealing a repeatable no brainer.
I also weight sort my cases, and bullets.
Powder gets weighted down to 0.01 grains.
Its embarrassing, but true.
Add me to the tight sphincter club.
I bought one of those Bench Source annealing machines.
A little tempilac followed by some quick setup made annealing a repeatable no brainer.
I also weight sort my cases, and bullets.
Powder gets weighted down to 0.01 grains.
Its embarrassing, but true.
Add me to the tight sphincter club.
Re: neck turning and it's issues
Steve, I have noticed the same. After first firing I checked with the ball mic. I still had the neck turner set from the first turn(nosler 7-08/260). I had noticed some brass flowing into the neck. From best memory it was more than .0005 and uneven measured at 12,3,6,9 o'clock. A quick run through the pumpkin and back to .01295-.01305. Don Neilson makes a very nice neck turner. I'm also a member of AA.
Steve, I have noticed the same. After first firing I checked with the ball mic. I still had the neck turner set from the first turn(nosler 7-08/260). I had noticed some brass flowing into the neck. From best memory it was more than .0005 and uneven measured at 12,3,6,9 o'clock. A quick run through the pumpkin and back to .01295-.01305. Don Neilson makes a very nice neck turner. I'm also a member of AA.
Re: neck turning and it's issues
Yeah, we all are. But some procedures gain more than others. For instance, I don't bother to anneal. But, I get accuracy I'm proud of, (more like sub quarter inch, I wouldn't spend any time on an inch and a half rifle) and I get at least ten reloads. Most of my brass is lost, not culled, but I segregate right at first, by weight and web thickness, and then scratch a little mark on the base so that they are always fired together.
The main consideration in accuracy is a good barrel, properly bedded. You can do many things, but you cannot make a silk purse out of a sows ear. The return on time invested is almost not observable, but it builds confidence that you did all you could. I wish, for instance, that I could get away from weighing powder, since all my benchrest friends say it is a waste of time? All things considered, this anal stuff is worth a lot. BB
Yeah, we all are. But some procedures gain more than others. For instance, I don't bother to anneal. But, I get accuracy I'm proud of, (more like sub quarter inch, I wouldn't spend any time on an inch and a half rifle) and I get at least ten reloads. Most of my brass is lost, not culled, but I segregate right at first, by weight and web thickness, and then scratch a little mark on the base so that they are always fired together.
The main consideration in accuracy is a good barrel, properly bedded. You can do many things, but you cannot make a silk purse out of a sows ear. The return on time invested is almost not observable, but it builds confidence that you did all you could. I wish, for instance, that I could get away from weighing powder, since all my benchrest friends say it is a waste of time? All things considered, this anal stuff is worth a lot. BB
Re: neck turning and it's issues
Another one from the AA club – good name for us.
I too find that the necks will become uneven again after the initial turn and firing, it just need to be cut down a very little bit ~0.0005” or less on the second turn. I am wondering if this will continue?
One thing that has not been mentioned is that I neck turn mostly for consistent neck tension which is very important if you want that low SDev number on your MVs.
Another one from the AA club – good name for us.
I too find that the necks will become uneven again after the initial turn and firing, it just need to be cut down a very little bit ~0.0005” or less on the second turn. I am wondering if this will continue?
One thing that has not been mentioned is that I neck turn mostly for consistent neck tension which is very important if you want that low SDev number on your MVs.
Re: neck turning and it's issues
I always use a nylon brush with a little WD40 (or comparable) on the neck interior, before pulling it over the expander ball as this can cause some deformation. Especially if you hear a squeak. Many benchresters don't use an expander ball but use hand neck dies over a precision bushing, which is what I do, on some of my accuracy stuff. Done right, (or all things being equal) I can't see a reason for subsequent additional neck turning? The main thing is to not work your brass any more than necessary. Considering neck tension is fine, to a point, but you have to use judgement on heavy recoilers, if you are stuffing the magazine.
I always use a nylon brush with a little WD40 (or comparable) on the neck interior, before pulling it over the expander ball as this can cause some deformation. Especially if you hear a squeak. Many benchresters don't use an expander ball but use hand neck dies over a precision bushing, which is what I do, on some of my accuracy stuff. Done right, (or all things being equal) I can't see a reason for subsequent additional neck turning? The main thing is to not work your brass any more than necessary. Considering neck tension is fine, to a point, but you have to use judgement on heavy recoilers, if you are stuffing the magazine.
Re: neck turning and it's issues
Steve - You are exactly right the second turning on the brass showed some of the brass with uneven thickness.
I broke out the tube micrometer to see the scope of what was going on, and its roughly 0.00025 to 0.00050 under the freshly turned neck. I figure that whole batch of brass is headed for the recycle bin before I need to consider turning it a third time.
The pieces that had substantial under-sized sections (25% or more) went into the recycle bin immediately.
Jeffvn
AA Unit!!!
Steve - You are exactly right the second turning on the brass showed some of the brass with uneven thickness.
I broke out the tube micrometer to see the scope of what was going on, and its roughly 0.00025 to 0.00050 under the freshly turned neck. I figure that whole batch of brass is headed for the recycle bin before I need to consider turning it a third time.
The pieces that had substantial under-sized sections (25% or more) went into the recycle bin immediately.
Jeffvn
AA Unit!!!
Re: neck turning and it's issues
Buzzboss,
If you can afford the Bench Source I highly recommend annealing.
I have seen some consistency and a bud of mine (top flight 6mmbr F-Class shooter)insists he can see annealing difference after only 2-3 firings and he shoots 0.1, 0.2, and is saddened by .3 groups.
What does the rest of the AA club use for powder scales?
Buzzboss,
If you can afford the Bench Source I highly recommend annealing.
I have seen some consistency and a bud of mine (top flight 6mmbr F-Class shooter)insists he can see annealing difference after only 2-3 firings and he shoots 0.1, 0.2, and is saddened by .3 groups.
What does the rest of the AA club use for powder scales?
Re: neck turning and it's issues
I throw, then trickle with an Ohaus 10-10 beam scale (my garage simply refuses to allow a digital to function properly.)
Jeffvn
I throw, then trickle with an Ohaus 10-10 beam scale (my garage simply refuses to allow a digital to function properly.)
Jeffvn
Re: neck turning and it's issues
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Jeffvn</div><div class="ubbcode-body">Steve - You are exactly right the second turning on the brass showed some of the brass with uneven thickness.
I broke out the tube micrometer to see the scope of what was going on, and its roughly 0.00025 to 0.00050 under the freshly turned neck. I figure that whole batch of brass is headed for the recycle bin before I need to consider turning it a third time.
The pieces that had substantial under-sized sections (25% or more) went into the recycle bin immediately.
Jeffvn
AA Unit!!! </div></div>
Thanks for the conformation guys. I'm sometimes embarrassed to admit this kind of stuff. As hard as I try to do everything just right there seems to be some new anomaly coming along that catches me off guard.
What are your theories of the cause of slightly uneven necks after they've been fired a bunch of times considering I did a full clean up of the neck on the first turn??
I covet my expensive Lapua brass,LOL. But I guess it's time I started culling the more rebellious ones.
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Jeffvn</div><div class="ubbcode-body">Steve - You are exactly right the second turning on the brass showed some of the brass with uneven thickness.
I broke out the tube micrometer to see the scope of what was going on, and its roughly 0.00025 to 0.00050 under the freshly turned neck. I figure that whole batch of brass is headed for the recycle bin before I need to consider turning it a third time.
The pieces that had substantial under-sized sections (25% or more) went into the recycle bin immediately.
Jeffvn
AA Unit!!! </div></div>
Thanks for the conformation guys. I'm sometimes embarrassed to admit this kind of stuff. As hard as I try to do everything just right there seems to be some new anomaly coming along that catches me off guard.
What are your theories of the cause of slightly uneven necks after they've been fired a bunch of times considering I did a full clean up of the neck on the first turn??
I covet my expensive Lapua brass,LOL. But I guess it's time I started culling the more rebellious ones.
Re: neck turning and it's issues
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Jeffvn</div><div class="ubbcode-body">I throw, then trickle with an Ohaus 10-10 beam scale (my garage simply refuses to allow a digital to function properly.)
Jeffvn </div></div>
Same here Jeff. One of these days to solidify my commitment to AA I'm going to get a tuned beam scale. I've been through 2 electronic scales and got tired of using my beam scale to verify the E scales weren't on the rag that day.
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Jeffvn</div><div class="ubbcode-body">I throw, then trickle with an Ohaus 10-10 beam scale (my garage simply refuses to allow a digital to function properly.)
Jeffvn </div></div>
Same here Jeff. One of these days to solidify my commitment to AA I'm going to get a tuned beam scale. I've been through 2 electronic scales and got tired of using my beam scale to verify the E scales weren't on the rag that day.
Re: neck turning and it's issues
Steve
I was thinking on the uneven brass issue, and can only attribute it to brass flowing to some spots and not others. I can't really nail it down from there, but it does flow (hence the need to trim). Once you get it moving its not so much predictable, at least by me.
If someone were MAJOR AA, they would mark the brass to index it into the chamber oriented the exact same way every time and watch to see if it flows evenly... If so, then we might be able to predict the thin spots.
Since my "cleaned" non-turned brass is running 0.015, but my turned brass runs 0.013, when it gets too thin for my tactical 7WSM use, I can turn it and use it for the F-Class rig. But when it gets too thin for the F-Class rig it goes to the recycle bin.
I love my tuned Ohaus 10-10. Scott got it to work like a champ. I think I paid all of $75.00 for it on E-Bay. Scott sometimes has spares in inventory (so he told me a few years ago when we talked). It might be worth the email to see if he does.
Jeffvn
Steve
I was thinking on the uneven brass issue, and can only attribute it to brass flowing to some spots and not others. I can't really nail it down from there, but it does flow (hence the need to trim). Once you get it moving its not so much predictable, at least by me.
If someone were MAJOR AA, they would mark the brass to index it into the chamber oriented the exact same way every time and watch to see if it flows evenly... If so, then we might be able to predict the thin spots.
Since my "cleaned" non-turned brass is running 0.015, but my turned brass runs 0.013, when it gets too thin for my tactical 7WSM use, I can turn it and use it for the F-Class rig. But when it gets too thin for the F-Class rig it goes to the recycle bin.
I love my tuned Ohaus 10-10. Scott got it to work like a champ. I think I paid all of $75.00 for it on E-Bay. Scott sometimes has spares in inventory (so he told me a few years ago when we talked). It might be worth the email to see if he does.
Jeffvn
Re: neck turning and it's issues
Yep too much of a brain strain for the likes of me. At least there's more uniformity than the unturned brass used to be.
Good idea transferring the brass from the tactical to the f-class rig!
Scott's the guy I plan on using and I think I'll use the 10-10 as well.
Have a great Christmas, Jeff!
Yep too much of a brain strain for the likes of me. At least there's more uniformity than the unturned brass used to be.
Good idea transferring the brass from the tactical to the f-class rig!
Scott's the guy I plan on using and I think I'll use the 10-10 as well.
Have a great Christmas, Jeff!
Re: neck turning and it's issues
I played around with this on my .308 I couldent tell a differnece. The more I studied it, I came to the conclusion above.
Factory or SAMMI chamber = No turning
Wildcat or cut for specific neck = Yes
I played around with this on my .308 I couldent tell a differnece. The more I studied it, I came to the conclusion above.
Factory or SAMMI chamber = No turning
Wildcat or cut for specific neck = Yes
Re: neck turning and it's issues
Neck turning for a factory chamber is quite useful if you do it properly for a bolt gun . It involves the turning operation and partial neck sizing . So a portion of the case neck near the shoulder is never sized at all. This is accomplished with a neck size only die and reducing it's travel down the neck and a body sizing die.
After first firing this unsized portion swells out to fit the chamber and stays there for the life of the case . Keep it short to reduce chambering friction. What this does is regain the increased neck to wall clearance caused by turning and centers the case better than before neck turning.
The donut is usually formed by not turning enough onto the shoulder.
I saw pictures on 6mm BR , of a turned neck case with a huge donut waiting to happen . When you turn you let the cutter just skim the very top edge of the shoulder and this indicates that the entire neck is turned. After that no donut will usually happen . It never has to me anyway. If you leave a slight ridge at the shoulder , upon firing it transfers to the inside to become the donut.
Neck turning for a factory chamber is quite useful if you do it properly for a bolt gun . It involves the turning operation and partial neck sizing . So a portion of the case neck near the shoulder is never sized at all. This is accomplished with a neck size only die and reducing it's travel down the neck and a body sizing die.
After first firing this unsized portion swells out to fit the chamber and stays there for the life of the case . Keep it short to reduce chambering friction. What this does is regain the increased neck to wall clearance caused by turning and centers the case better than before neck turning.
The donut is usually formed by not turning enough onto the shoulder.
I saw pictures on 6mm BR , of a turned neck case with a huge donut waiting to happen . When you turn you let the cutter just skim the very top edge of the shoulder and this indicates that the entire neck is turned. After that no donut will usually happen . It never has to me anyway. If you leave a slight ridge at the shoulder , upon firing it transfers to the inside to become the donut.
Re: neck turning and it's issues
Yeah, maybe? But, this is where the general rule, outside turn, versus inside ream comes into play. If you have to seat past the neck area, (deeper) and you have developed a donut, which you can feel, when seating the bullet, (on an arbor press) I wouldn't be afraid to eliminate it with a reamer. That's why the 300WM case with it's short neck guarantees that you must seat your bullets past the donut. BB
Yeah, maybe? But, this is where the general rule, outside turn, versus inside ream comes into play. If you have to seat past the neck area, (deeper) and you have developed a donut, which you can feel, when seating the bullet, (on an arbor press) I wouldn't be afraid to eliminate it with a reamer. That's why the 300WM case with it's short neck guarantees that you must seat your bullets past the donut. BB
Re: neck turning and it's issues
Country,
I tried the same thing only with a FL bushing die with the bushing allowed to float ~0.15 off the shoulder.
I mentioned my technique on a couple of sites and it was promptly shot down as encouraging a dread doughnut (DD).
I am still not sure why as the tolerances created by partial turning and partial sizing should be bigger than a DD?
This is somewhat embarrassing as I am an accomplished shooter/reloader, but I fully admit to not understanding the scope of a DD.
Perhaps someone could help enlighten me as to what is going on here?
Peace
Country,
I tried the same thing only with a FL bushing die with the bushing allowed to float ~0.15 off the shoulder.
I mentioned my technique on a couple of sites and it was promptly shot down as encouraging a dread doughnut (DD).
I am still not sure why as the tolerances created by partial turning and partial sizing should be bigger than a DD?
This is somewhat embarrassing as I am an accomplished shooter/reloader, but I fully admit to not understanding the scope of a DD.
Perhaps someone could help enlighten me as to what is going on here?
Peace
Re: neck turning and it's issues
It's a case of TMI, too much information. I stated my opinion above, a couple days ago. If you want to turn your necks, you need to understand why you are doing it and do it correctly, and again, (in my opinion) unless you have a tight neck, and you need a specific case neck thickness..... you are wasting your time and asking for trouble. If your gun didn't come with a specified neck diameter, and you feel that you must turn the necks, just take off a little bit and let it go at that. TMI/BB
It's a case of TMI, too much information. I stated my opinion above, a couple days ago. If you want to turn your necks, you need to understand why you are doing it and do it correctly, and again, (in my opinion) unless you have a tight neck, and you need a specific case neck thickness..... you are wasting your time and asking for trouble. If your gun didn't come with a specified neck diameter, and you feel that you must turn the necks, just take off a little bit and let it go at that. TMI/BB
Re: neck turning and it's issues
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: X-fan</div><div class="ubbcode-body">Country,
I tried the same thing only with a FL bushing die with the bushing allowed to float ~0.15 off the shoulder.
I mentioned my technique on a couple of sites and it was promptly shot down as encouraging a dread doughnut (DD).
I am still not sure why as the tolerances created by partial turning and partial sizing should be bigger than a DD?
This is somewhat embarrassing as I am an accomplished shooter/reloader, but I fully admit to not understanding the scope of a DD.
Perhaps someone could help enlighten me as to what is going on here?Peace </div></div>
Partial neck sizing will not cause a donut as it is allowing the brass to expand out as far as it can. If the case neck is turned properly onto the shoulder or inside neck reamed as others say then no donut can result unless the brass was very uneven on the inside to start with. There is nothing wrong with the partial length neck sizing idea for a bolt gun with good caming action. The problem is most that nock it don't fully understand the principle. In two cartridges I use a Lee collet die with a spacing washer over the case to achieve the partial lenghth size and in another a bushing neck die .
The main issue is that you don't want to make the unsized section too long as it starts to hamper chambering a bit. . You want it to engauge just as the bolt is nearly closed . Each case feels a bit like the case needs sizing but it is just the neck jaming in. Eventually it gets harder and you need to go back into your preset body sizing die just to make sure the shoulder is not growing too long. It is important to set your body sizing die first with a tight case with no neck bulge to start as it is very hard to feel the correct bolt closure on a sized case with the extra friction of a partial sized neck that has already been fired a few times . It can lead to oversizing the case by accident . Although even if it does happen the fact that the bulge resists chambering to some degree usually means the case is well against the bolt face anyway.
Some cases can have a slight internal donut from new and if you don't seat a bullet past the shoulder neck junction it does not do much harm . However if you use a neck expander for any reason the donut can move to the outside to some degree and when you neck size move back inside to some degree. When you neck turn and leave a ridge near the shoulder neck junction it turns into an internal donut on firing . I also think that some case designs that flow brass forward could add to the forming of a donut right where the shoulder neck junction , sizing might help also .
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: X-fan</div><div class="ubbcode-body">Country,
I tried the same thing only with a FL bushing die with the bushing allowed to float ~0.15 off the shoulder.
I mentioned my technique on a couple of sites and it was promptly shot down as encouraging a dread doughnut (DD).
I am still not sure why as the tolerances created by partial turning and partial sizing should be bigger than a DD?
This is somewhat embarrassing as I am an accomplished shooter/reloader, but I fully admit to not understanding the scope of a DD.
Perhaps someone could help enlighten me as to what is going on here?Peace </div></div>
Partial neck sizing will not cause a donut as it is allowing the brass to expand out as far as it can. If the case neck is turned properly onto the shoulder or inside neck reamed as others say then no donut can result unless the brass was very uneven on the inside to start with. There is nothing wrong with the partial length neck sizing idea for a bolt gun with good caming action. The problem is most that nock it don't fully understand the principle. In two cartridges I use a Lee collet die with a spacing washer over the case to achieve the partial lenghth size and in another a bushing neck die .
The main issue is that you don't want to make the unsized section too long as it starts to hamper chambering a bit. . You want it to engauge just as the bolt is nearly closed . Each case feels a bit like the case needs sizing but it is just the neck jaming in. Eventually it gets harder and you need to go back into your preset body sizing die just to make sure the shoulder is not growing too long. It is important to set your body sizing die first with a tight case with no neck bulge to start as it is very hard to feel the correct bolt closure on a sized case with the extra friction of a partial sized neck that has already been fired a few times . It can lead to oversizing the case by accident . Although even if it does happen the fact that the bulge resists chambering to some degree usually means the case is well against the bolt face anyway.
Some cases can have a slight internal donut from new and if you don't seat a bullet past the shoulder neck junction it does not do much harm . However if you use a neck expander for any reason the donut can move to the outside to some degree and when you neck size move back inside to some degree. When you neck turn and leave a ridge near the shoulder neck junction it turns into an internal donut on firing . I also think that some case designs that flow brass forward could add to the forming of a donut right where the shoulder neck junction , sizing might help also .
Re: neck turning and it's issues
Roger that Country.
I actually do bump the shoulder 2 thou every time, but I unscrew the bushing lock allowing it to float off the neck/shoulder junction approx. 0.15". Sort of cool because it centers itself on the case regardless of the die.
I first used it with a 338RUM with concentricity problems (the brass). You are right it did create some resistance (a nice crush fit) even though the headspace was right...Never got recessive, but then again the Remington brass lived a short and violent life. What was sort of neat is the crush fit meant the case was forced dead center and the bullet was looking down the bore...
I did run into some concentricity issues and blamed it on my setup...turned out to be a bent spindle...Some day I will try it again.
Do you think the method offers any Merit?
Peace
Roger that Country.
I actually do bump the shoulder 2 thou every time, but I unscrew the bushing lock allowing it to float off the neck/shoulder junction approx. 0.15". Sort of cool because it centers itself on the case regardless of the die.
I first used it with a 338RUM with concentricity problems (the brass). You are right it did create some resistance (a nice crush fit) even though the headspace was right...Never got recessive, but then again the Remington brass lived a short and violent life. What was sort of neat is the crush fit meant the case was forced dead center and the bullet was looking down the bore...
I did run into some concentricity issues and blamed it on my setup...turned out to be a bent spindle...Some day I will try it again.
Do you think the method offers any Merit?
Peace
Re: neck turning and it's issues
I do think the whole overall principle has merit but there is several die systems that could work so it is hard to say which one is best. Generaly speaking partial neck length sizing does work in a bolt gun and I have used Lee collet dies and Redding bushing dies to achieve it.
I have been doing it for a very long time and it's my normal way to reload now for my bolt guns. It is one of those things that you have to try for yourself and see if you like it and if it infact it helps accuracy. You can't say what will definately work in every gun it just is not possible as they all vary in what they like.
Another trick I use is to place a large O ring under the Lee Collet neck sizing die lock ring so the whole die floats to a small degree , not much but you can see it move sideways a small amount at full size pressure.
I do think the whole overall principle has merit but there is several die systems that could work so it is hard to say which one is best. Generaly speaking partial neck length sizing does work in a bolt gun and I have used Lee collet dies and Redding bushing dies to achieve it.
I have been doing it for a very long time and it's my normal way to reload now for my bolt guns. It is one of those things that you have to try for yourself and see if you like it and if it infact it helps accuracy. You can't say what will definately work in every gun it just is not possible as they all vary in what they like.
Another trick I use is to place a large O ring under the Lee Collet neck sizing die lock ring so the whole die floats to a small degree , not much but you can see it move sideways a small amount at full size pressure.
Re: neck turning and it's issues
I find that new Lapua brass varies in neck wall thickness of .005. I turn all my new brass to the smallest wall thickness. Some cases receive a .005 cut while others hardly have the annealing discoloration skimmed off.
After turning, I use a .335 bushing which gives me a consistent .002 neck tension for seating. (.308). I respectfully disagree with folks that say neck turning is not necessary and is only for chambers requiring it. If more accuracy is your goal, then consistent neck tension is important. You just don't get that with out of the box brass.
I have definitely seen an improvement on paper at 600 yards (my regular practice distance). I use the 21st Century lathe setup powered by my DeWalt.
I find that new Lapua brass varies in neck wall thickness of .005. I turn all my new brass to the smallest wall thickness. Some cases receive a .005 cut while others hardly have the annealing discoloration skimmed off.
After turning, I use a .335 bushing which gives me a consistent .002 neck tension for seating. (.308). I respectfully disagree with folks that say neck turning is not necessary and is only for chambers requiring it. If more accuracy is your goal, then consistent neck tension is important. You just don't get that with out of the box brass.
I have definitely seen an improvement on paper at 600 yards (my regular practice distance). I use the 21st Century lathe setup powered by my DeWalt.
Re: neck turning and it's issues
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Leaddog</div><div class="ubbcode-body">
After turning, I use a .335 bushing which gives me a consistent .002 neck tension for seating. (.308). I respectfully disagree with folks that say neck turning is not necessary and is only for chambers requiring it. If more accuracy is your goal, then consistent neck tension is important. You just don't get that with out of the box brass.
</div></div>
I guess I understand this line of reasoning? When working with imperfect gear, anything you do with an aim towards uniformity is probably of some benefit? Just think how much improvement you would see at 600 yards if you also had a tight neck?
In the pursuit of pure accuracy, there is just so much you can do with a factory barrel. BB
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Leaddog</div><div class="ubbcode-body">
After turning, I use a .335 bushing which gives me a consistent .002 neck tension for seating. (.308). I respectfully disagree with folks that say neck turning is not necessary and is only for chambers requiring it. If more accuracy is your goal, then consistent neck tension is important. You just don't get that with out of the box brass.
</div></div>
I guess I understand this line of reasoning? When working with imperfect gear, anything you do with an aim towards uniformity is probably of some benefit? Just think how much improvement you would see at 600 yards if you also had a tight neck?
In the pursuit of pure accuracy, there is just so much you can do with a factory barrel. BB
Re: neck turning and it's issues
Buzz- I'm running two 10 twist barrels. A Hart and a Spencer, both tight bores. Didn't see a need for a .337 neck when I had them chambered. Hardly imperfect gear as you say. A .340 neck is just fine for an F T/R .308.
I shoot the Berger 185 LRBT's with good success.
Buzz- I'm running two 10 twist barrels. A Hart and a Spencer, both tight bores. Didn't see a need for a .337 neck when I had them chambered. Hardly imperfect gear as you say. A .340 neck is just fine for an F T/R .308.
I shoot the Berger 185 LRBT's with good success.
Re: neck turning and it's issues
Okay, my apologies. My comprehension is sometimes imperfect. BB
Okay, my apologies. My comprehension is sometimes imperfect. BB
Re: neck turning and it's issues
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: X-fan</div><div class="ubbcode-body">Leaddog,
What NT tool do you use?
Great thread all.
Peace
</div></div>
X Fan - I use the 21st Century. Google it up. It's a good setup.
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: X-fan</div><div class="ubbcode-body">Leaddog,
What NT tool do you use?
Great thread all.
Peace
</div></div>
X Fan - I use the 21st Century. Google it up. It's a good setup.
Re: neck turning and it's issues
Remaction,
So your drawing says incorrect neck turning essentially creates the dread doughnut?
Thanks for the drawing!
Remaction,
So your drawing says incorrect neck turning essentially creates the dread doughnut?
Thanks for the drawing!
Re: neck turning and it's issues
Well.......it's one of the causes. When I neck turn I use a K&M tool that has a cutting edge on the front of the mandrel. When I am making my first neck cut, after expanding the inside to fit the mandrel correctly, the mandrel cutter always has to cut through a small "donut" at the base of the neck. This is before a neck cut has been made, but however, on those casings, I have already set the shoulder back to shorten the round (30x47 which is a shortened .308). So it appears that the shortening of the case by pushing the shoulder down has created a "donut" also. Why? I'm not sure. Obviously, after expanding the inside of the neck, some brass "springback" occurs which alows the donut to be smaller than the rest of the neck. This is something to consider if you are dealing with wildcats.
Well.......it's one of the causes. When I neck turn I use a K&M tool that has a cutting edge on the front of the mandrel. When I am making my first neck cut, after expanding the inside to fit the mandrel correctly, the mandrel cutter always has to cut through a small "donut" at the base of the neck. This is before a neck cut has been made, but however, on those casings, I have already set the shoulder back to shorten the round (30x47 which is a shortened .308). So it appears that the shortening of the case by pushing the shoulder down has created a "donut" also. Why? I'm not sure. Obviously, after expanding the inside of the neck, some brass "springback" occurs which alows the donut to be smaller than the rest of the neck. This is something to consider if you are dealing with wildcats.
Re: neck turning and it's issues
Remaction – I know what you have drawn is what is what is normally quoted for the cause of donuts, but after working with neck turning for a while, I am not sure that this is the only reason. The reason I say this is because I turn my neck all the way up to the slope of the shoulder and I neck size with the Redding Type S die which does not size the area next to the shoulder but the donuts form anyway.
My own feeling is that although improper neck turning may be part of the cause of some donuts, I think some of the material that forms the donut is actually caused by the brass moving forward from the shoulder into the neck as you fire the round i.e. the same reason why neck gets longer.
Remaction – I know what you have drawn is what is what is normally quoted for the cause of donuts, but after working with neck turning for a while, I am not sure that this is the only reason. The reason I say this is because I turn my neck all the way up to the slope of the shoulder and I neck size with the Redding Type S die which does not size the area next to the shoulder but the donuts form anyway.
My own feeling is that although improper neck turning may be part of the cause of some donuts, I think some of the material that forms the donut is actually caused by the brass moving forward from the shoulder into the neck as you fire the round i.e. the same reason why neck gets longer.
Re: neck turning and it's issues
Jlow, I agree, but I thought the drawing would help explain the neck turning cause. The only time I'm really careful to avoid the donut is in my tight necked guns, as I wouldn't want the deep seating of a bullet to push a donut outward and cause pressures to rise.
Jlow, I agree, but I thought the drawing would help explain the neck turning cause. The only time I'm really careful to avoid the donut is in my tight necked guns, as I wouldn't want the deep seating of a bullet to push a donut outward and cause pressures to rise.
Re: neck turning and it's issues
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: remaction</div><div class="ubbcode-body">A picture is sometimes worth a thousand words. There is good info in the above thread. Use this in conjunction with the above thread. No use in me repeating anything.
</div></div>
Nice work and very helpfull.
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: remaction</div><div class="ubbcode-body">A picture is sometimes worth a thousand words. There is good info in the above thread. Use this in conjunction with the above thread. No use in me repeating anything.
Nice work and very helpfull.
