I know that when you resize a fire formed case to be used in the same rifle you should set the shoulder back about 002". By adjusting your fl resize die to do this are you effectively making it a neck sizing die or would you have to adjust a neck sizing die the same way. I guess what I'm asking is if a neck die pushes the shoulder back or not.
resizing die
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Sunray
Member
2 thou isn't enough to worry about. That's slightly bigger than a hair.
Set all your dies up so the shell holder just kisses the bottom of the die with the ram all the way up and you'll be fine.
Now if you want your FL die to neck size only, that takes a bunch of trial and error fiddling to do.
A neck sizer doesn't touch the shoulders at all. If you're loading for a semi, pump or lever action, you cannot neck size only.
Set all your dies up so the shell holder just kisses the bottom of the die with the ram all the way up and you'll be fine.
Now if you want your FL die to neck size only, that takes a bunch of trial and error fiddling to do.
A neck sizer doesn't touch the shoulders at all. If you're loading for a semi, pump or lever action, you cannot neck size only.
Blue68f100
Member
Most neck sizing dies do not push the shoulder back. There are some that do though. Depending on brass you may be able to get 2-3 neck sizing done before the shoulder needs to be moved back.
Running the die down to the shell plate is not always the best way since you can overly move the shoulder back a long ways. You will need to measure your before and after to know where your at. 0.002-0.003" is not much but does make a difference in chambering, particularly if this is for a simi-auto or lever gun.
Running the die down to the shell plate is not always the best way since you can overly move the shoulder back a long ways. You will need to measure your before and after to know where your at. 0.002-0.003" is not much but does make a difference in chambering, particularly if this is for a simi-auto or lever gun.
Reducing the length of the case from the shoulder to the case head .002" is an option. For the 30/06 chamber, in the perfect world, a case that is sized to minimum length/full length sized will have a difference in length of .005". Meaning the chamber is .005" longer from the shoulder of the chamber to the bolt face than the case from the shoulder of the case to the case head.
Again, I have a chamber that is .011" longer than a go-gage length chamber. When sizing cases for that chamber I adjust the die off the shell holder .014". The .014: give me the magic .002" clearance, and by not insisting on full length sizing I reduce the amount of effort it takes to size the case. then there is that part about finding cases that are longer between the shoulder and case head: I use 280 Remington cases, I can not miss, the 280 Remington case is .051" longer from the shoulder of the case to the case head than the 30/06.
F. Guffey
No, you are sizing the whole case, you just are not pushing the shoulder back as far as the die would allow.
.002 is great for bolt guns, but might be a bit tight for autos.
Standard neck dies size the neck only.
Walkalong's correct.
Minimal fired bottleneck case full length sizing gives longer case life and better accuracy. The more a fired case's dimensions are reduced, especially its headspace, the more it stretches the case at its pressure ring every time it's fired. It gets worse if the chamber headspace is at or near maximum and the sizing die's set to just touch the bottom of the die when the press ram's at the top of its stroke; case head separation is soon at hand.
If you completely understand how case dimensions change when first fired, then through the full length sizing process, then fired again, you'll understand why minimal fired bottleneck case sizing is best. Otherwise, well...... learning helps.
Die instructions say to have the die bottom touch the shell holder only to ensure fired cases resized in their dies will fit the shortest chamber headspaces typically encountered.
You cannot use a bottleneck FL die to only neck size a fired case. The case shoulder will be squished forward several thousandths while the body's sized down making the case hard to rechamber, if at all. Sure cause of reduced accuracy.
There are neck sizing dies that use bushings that also set the case shoulder back as desired. Bushing neck diameters vary depending on the neck grip desired.
Minimal fired bottleneck case full length sizing gives longer case life and better accuracy. The more a fired case's dimensions are reduced, especially its headspace, the more it stretches the case at its pressure ring every time it's fired. It gets worse if the chamber headspace is at or near maximum and the sizing die's set to just touch the bottom of the die when the press ram's at the top of its stroke; case head separation is soon at hand.
If you completely understand how case dimensions change when first fired, then through the full length sizing process, then fired again, you'll understand why minimal fired bottleneck case sizing is best. Otherwise, well...... learning helps.
Die instructions say to have the die bottom touch the shell holder only to ensure fired cases resized in their dies will fit the shortest chamber headspaces typically encountered.
You cannot use a bottleneck FL die to only neck size a fired case. The case shoulder will be squished forward several thousandths while the body's sized down making the case hard to rechamber, if at all. Sure cause of reduced accuracy.
There are neck sizing dies that use bushings that also set the case shoulder back as desired. Bushing neck diameters vary depending on the neck grip desired.
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gamestalker
member
Couple of things here that might help you understand how dies function, or rather, what they do.
A neck die doesn't touch the shoulder at all. It's only function is to resize the diameter of the neck. It doesn't touch the neck or the body of the brass what so ever.
A FL resizing die sizes changes every measureable aspect of the brass. It squeeze the body and the neck down smaller, and it also pushes the shoulder down or up depending on how the die is adjusted. In other words, as you thread a FL die down it begins squeezing the case body in. So as the body gets pushed in, the brass that get displaced has to go some where, thus it pushes the shoulders up. Then as the die gets continued to be threaded down, at some point the shoulders of the brass will begin to make contact with the shoulder in the die, thus pushing the should down further and further the more the die is threaded down.
Hope this helps
GS
A neck die doesn't touch the shoulder at all. It's only function is to resize the diameter of the neck. It doesn't touch the neck or the body of the brass what so ever.
A FL resizing die sizes changes every measureable aspect of the brass. It squeeze the body and the neck down smaller, and it also pushes the shoulder down or up depending on how the die is adjusted. In other words, as you thread a FL die down it begins squeezing the case body in. So as the body gets pushed in, the brass that get displaced has to go some where, thus it pushes the shoulders up. Then as the die gets continued to be threaded down, at some point the shoulders of the brass will begin to make contact with the shoulder in the die, thus pushing the should down further and further the more the die is threaded down.
Hope this helps
GS
By design the neck sizing die will not touch the shoulder of the case, by design the neck sizing die will not touch the case body.
It is assumed the shoulder on the case moves, if the shoulder moves the case body below it would compress when the case is sized. I fire many cases that have shoulder that do not move, I like that.
F. Guffey
ArchAngelCD
Member.
IMO buying a neck die for ammo shot in an 03 Springfield is a waste of money. Neck sizing is overrated in most cases IMO but I'm sure I will get yelled at for saying that. If you were shooting long distance with a match chambered rifle you might see a difference in accuracy with neck sizing. For an only military rifle, not so much...
A few years ago, match winners and record setters in the benchrest disciplines saw a difference in their groups when they switched from neck only to full length sizing their fired cases. Smallest groups stayed the same size. Largest groups weren't as big. Sizing down fired case dimensions minimally is all that's needed.
Why it took them so long to figure that proper full length sizing is best for accuracy is beyond me. Top ranked ompetitors in high power rifle disciplines learned that back in the 1950's or earlier. Thanks to Sierra Bullets' tests with all sorts of fired case resizing tools and techniques. More often than not, new cases shoot bullets more accurate than fired then neck-only resized ones.
Once you've learned how bottleneck cases fit the chamber when fired and there's no such thing as perfectly round cases and chambers, it's easy to understand why proper full length sizing dies plus their setup and use techniques produce best accuracy as well as very long case life. A recent benchrest record was set with cases that had been full length sized about 100 times.
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Andrew Leigh
Member
Or you can have the best of both worlds. You can full length size your brass to your unique chambers headspace. The below write-up is from the www.gscustom.co.za site. I can never find it on their website, it is well hidden, so I put it into MS Word so I can lay my hands on it. Italicized text is my opinion.
It is very common that the sizing die is not set up to match the individual rifle chamber. This leads to all manners of difficulty like the ammunition displaying signs of overpressure while speeds are below maximum or the case necks tearing on firing.
There are many recommendations and apparent fix’s like neck sizing, increasing or reducing crimp, blaming the cases for either being too old or to new, rejecting specific brands of brass as being not suitable are all symptoms of a poorly setup sizing die.
Here is what must be done and must be followed to the letter, do not omit any step. The setup is a system much like a recipe. Miss one of the ingredients or steps and the recipe will fail.
1. Always use the same shell holder with the same sizing die.
2. Ensure that the cases are within the length specifications.
3. Insert the sizing die and screw it down until it lightly touches the shell holder when in the highest position.
4. Lubricate a case and size it.
5. Thoroughly clean the case of all lubricant and chamber the case. Mauser type actions will require that insert the case into the magazine so that the slot extractor claw can pick the case up for chambering.
6. If the bolt cams over as if there is nothing in the chamber then stick a layer of masking tape to the base of the case and repeat the exercise. If the bolt cams over hard then you will need to remove a layer from the top of the case.
7. Continue to add masking tape until you feel drag on the bolt on closing and that there are clear indications that the bolt is placing pressure on the masking tape. I remove the firing pin from the bolt so that I can feel the cam over pressure, the force required to compress the firing pin spring I believe overrides ones “feel”.
8. Measure the combined thickness of the layers of masking tape and set the sizing die away from the shell holder by the same amount. Use a feeler gauge to get the correct distance.
9. Lock the die in position and never set the die again for that specific rifle.
The general idea is to duplicate the distance between the shoulder of the specific rifle chamber and the slot face with the shell holder and sizing die. If you do not have dies with lock rings fitted with lock screws then sell the die set to someone you don’t like and get the right dies.
It will be necessary to fire form all cases once before the effect of the new and correct settings are realised. Do not reset the sizing die. New cases must be sized before loading. Do not reset the sizing die.
When the bolt closing resistance get too stiff on closing then it is either time to trim to length or to anneal case necks. Do not reset the sizing die.
All my calibres are set this way.
It is very common that the sizing die is not set up to match the individual rifle chamber. This leads to all manners of difficulty like the ammunition displaying signs of overpressure while speeds are below maximum or the case necks tearing on firing.
There are many recommendations and apparent fix’s like neck sizing, increasing or reducing crimp, blaming the cases for either being too old or to new, rejecting specific brands of brass as being not suitable are all symptoms of a poorly setup sizing die.
Here is what must be done and must be followed to the letter, do not omit any step. The setup is a system much like a recipe. Miss one of the ingredients or steps and the recipe will fail.
1. Always use the same shell holder with the same sizing die.
2. Ensure that the cases are within the length specifications.
3. Insert the sizing die and screw it down until it lightly touches the shell holder when in the highest position.
4. Lubricate a case and size it.
5. Thoroughly clean the case of all lubricant and chamber the case. Mauser type actions will require that insert the case into the magazine so that the slot extractor claw can pick the case up for chambering.
6. If the bolt cams over as if there is nothing in the chamber then stick a layer of masking tape to the base of the case and repeat the exercise. If the bolt cams over hard then you will need to remove a layer from the top of the case.
7. Continue to add masking tape until you feel drag on the bolt on closing and that there are clear indications that the bolt is placing pressure on the masking tape. I remove the firing pin from the bolt so that I can feel the cam over pressure, the force required to compress the firing pin spring I believe overrides ones “feel”.
8. Measure the combined thickness of the layers of masking tape and set the sizing die away from the shell holder by the same amount. Use a feeler gauge to get the correct distance.
9. Lock the die in position and never set the die again for that specific rifle.
The general idea is to duplicate the distance between the shoulder of the specific rifle chamber and the slot face with the shell holder and sizing die. If you do not have dies with lock rings fitted with lock screws then sell the die set to someone you don’t like and get the right dies.
It will be necessary to fire form all cases once before the effect of the new and correct settings are realised. Do not reset the sizing die. New cases must be sized before loading. Do not reset the sizing die.
When the bolt closing resistance get too stiff on closing then it is either time to trim to length or to anneal case necks. Do not reset the sizing die.
All my calibres are set this way.
With annealing machines so prevalent now that seems to be the preferred method these days. I used to adjust the sizer to the brass as it work hardened, and then of course would have to adjust it again for new brass or when I did anneal. I came the the eventual conclusion that it is better to anneal as needed instead of adjusting the die and annealing only when it got too work hardened. Some prefer to anneal every time, but I think after every third firing is enough. YMMV of course. If I had one of those fancy annealers I might do it every time as well.
Woodworker74
Member
"6. If the bolt cams over as if there is nothing in the chamber then stick a layer of masking tape to the base of the case and repeat the exercise. If the bolt cams over hard then you will need to remove a layer from the top of the case."
What if you're at the point where full length re-sized brass is hard to chamber? I'm having this issue with brass that's been fired 3 times in my 300 WSM (neck sized up till now after initial firing). Trim length is good and full length re-sizing is still giving me quite a bit of resistance when the bolt cams over to close. Am I not setting the die down far enough in the press? It's making contact with the shell holder, plus a 1/4 turn, so I'm not sure what else I can adjust?? Am I wrong that when it makes full contact with the shell holder, it has reached it's maximum point of travel and will therefore not size the case any further?
What if you're at the point where full length re-sized brass is hard to chamber? I'm having this issue with brass that's been fired 3 times in my 300 WSM (neck sized up till now after initial firing). Trim length is good and full length re-sizing is still giving me quite a bit of resistance when the bolt cams over to close. Am I not setting the die down far enough in the press? It's making contact with the shell holder, plus a 1/4 turn, so I'm not sure what else I can adjust?? Am I wrong that when it makes full contact with the shell holder, it has reached it's maximum point of travel and will therefore not size the case any further?
Andrew Leigh
Member
We are talking fractions here. The only consistent way that I have found to F/L size brass is to get the press to cam over with moderate pressure. This assures you that the same pressure is applied to every stroke. If you do not cam over you are reliant on you arm to apply the same pressure which is almost impossible.
Does that make sense?
If brass gets too work hardened it resists sizing and can be hard to move the shoulder back enough chamber easily again.
Check the sizer and shell holder when actually sizing a case to make sure it has all the slack out.
Check the sizer and shell holder when actually sizing a case to make sure it has all the slack out.
Indeed, "fractions" are critical in getting the case sized "just right" to fit the chamber. Here's my take on those thousandths of an inch measurements.
First off, precise measurement of case headspace (head to shoulder reference diameter) is needed if long case life is important. The important measurement is how much the shoulder's set back after full length sizing the fired case. Too much causes excessive case stretching at its pressure ring when fired as well as making the case head more out of square as one side of the case stretches more than the other. Too little and the case may be a tight fit and a stripped bolt won't close from the weight of its bolt handle twisting it into battery without forcing it; a well known cause of accuracy degradation. Use a gauge such as the RCBS Precision Mic or the Hornady LNL. A plastic bushing with the inside diameter that of someplace on the case shoulder can also be used with a caliper. It's the difference in case headspace from fired to resized that's important; actual case headspace is not. Note that actual chamber headspace at its shoulder is typically .001" greater than that of a fired case.
Changing the die position the popular way 1/4 turn moves it about .018"; way too much. Instead, put one of these labels on your die's lock ring the you can adjust it in very tiny but precise increments:
http://s860.photobucket.com/user/jepp2/media/DieAdjustment-1.jpg.html
Second, using the press with the die set as desired so resized case headspace is reasonably consistent. Uniform coatings of case lube help a lot as does keeping the ram at its full height long enough to let the spring of the press pull the die down as far at it'll go for each stroke of its handle. Stopping the die at the same place relative to the shell holder helps, too. Redding make a set of shell holders for many cartridges that have top heights in .002" steps above the .125" standard. Using the right one to stop the ram with the shell holder hard against the die bottom for desired sized case headspace results in very uniform dimensions with less than a .001" spread.
Third, the bolt face. If it's out of square with one side a thousandth or more back than the opposite side, that's how a new case head flattens up against it. No sizing process squares it back up. If it's rechambered 180 degrees out from how it was fired, the bolt will typically bind as the case and face high points are aligned with each other. Which is why some rifle's fired cases need to have their shoulders set back a bit more to allow for out of square bolt faces.
Finally, the bolt must close freely on all chambered live rounds. If it binds, its face will twist the bolt head at random places in its fit to the receiver. That causes the barrel to whip and wiggle at different angles from shot to shot. Accuracy will suffer and's easily observed in very accurate stuff.
Has anybody ever measured a rimless bottleneck cartridge full length sizing die for headspace? (Yes, dies can have headspace just like barrel chambers.) That's the distance from its shoulder reference to the bottom of the shell holder when the shell holder is against its bottom. I've got seven .308 Win full length sizing dies and their headspace is about .005" less than a .308 Win. GO headspace gauge at 1.630". Cases full length sized in them when the shell holder stops against the die bottom have headspace about 1.627". Learned all about that stuff years ago thinking I could set a full length die in the press screwing it down so it just stopped against a GO headspace gauge. Fired cases sized in it set that way would not chamber in rifles with 1.630" to 1.631" chamber headspace.
First off, precise measurement of case headspace (head to shoulder reference diameter) is needed if long case life is important. The important measurement is how much the shoulder's set back after full length sizing the fired case. Too much causes excessive case stretching at its pressure ring when fired as well as making the case head more out of square as one side of the case stretches more than the other. Too little and the case may be a tight fit and a stripped bolt won't close from the weight of its bolt handle twisting it into battery without forcing it; a well known cause of accuracy degradation. Use a gauge such as the RCBS Precision Mic or the Hornady LNL. A plastic bushing with the inside diameter that of someplace on the case shoulder can also be used with a caliper. It's the difference in case headspace from fired to resized that's important; actual case headspace is not. Note that actual chamber headspace at its shoulder is typically .001" greater than that of a fired case.
Changing the die position the popular way 1/4 turn moves it about .018"; way too much. Instead, put one of these labels on your die's lock ring the you can adjust it in very tiny but precise increments:
http://s860.photobucket.com/user/jepp2/media/DieAdjustment-1.jpg.html
Second, using the press with the die set as desired so resized case headspace is reasonably consistent. Uniform coatings of case lube help a lot as does keeping the ram at its full height long enough to let the spring of the press pull the die down as far at it'll go for each stroke of its handle. Stopping the die at the same place relative to the shell holder helps, too. Redding make a set of shell holders for many cartridges that have top heights in .002" steps above the .125" standard. Using the right one to stop the ram with the shell holder hard against the die bottom for desired sized case headspace results in very uniform dimensions with less than a .001" spread.
Third, the bolt face. If it's out of square with one side a thousandth or more back than the opposite side, that's how a new case head flattens up against it. No sizing process squares it back up. If it's rechambered 180 degrees out from how it was fired, the bolt will typically bind as the case and face high points are aligned with each other. Which is why some rifle's fired cases need to have their shoulders set back a bit more to allow for out of square bolt faces.
Finally, the bolt must close freely on all chambered live rounds. If it binds, its face will twist the bolt head at random places in its fit to the receiver. That causes the barrel to whip and wiggle at different angles from shot to shot. Accuracy will suffer and's easily observed in very accurate stuff.
Has anybody ever measured a rimless bottleneck cartridge full length sizing die for headspace? (Yes, dies can have headspace just like barrel chambers.) That's the distance from its shoulder reference to the bottom of the shell holder when the shell holder is against its bottom. I've got seven .308 Win full length sizing dies and their headspace is about .005" less than a .308 Win. GO headspace gauge at 1.630". Cases full length sized in them when the shell holder stops against the die bottom have headspace about 1.627". Learned all about that stuff years ago thinking I could set a full length die in the press screwing it down so it just stopped against a GO headspace gauge. Fired cases sized in it set that way would not chamber in rifles with 1.630" to 1.631" chamber headspace.
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Woodworkers questions:
But wait; there's a solution.
Every once in a great while, someone ends up with full length sizing die whose headspace is a bit longer than maximum. And that's coupled with a shell holder whose height is a bit higher than the .125" spec. Their rifle's chamber headspace is a couple thousandths short of minimum specs for headspace. Cases full length sized in that die will be hard to chamber, if they can be at all.
The solution is to reduce the die's headspace so fired case shoulders will be set back further. Grind off a few thousandths inch off the bottom of the die. Or, grind off a few thousandths off the top of the shell holder then mark it for use with that die only. I'd grind off the bottom of the die so the shell holder can be used normally with other cartridges.
Measure the shell holder's top edge to the bottom where the case head rests with a caliper. If it's more than .126" (typical industry limit), grind if off .002" If it's .126" or less, grind off the die's bottom a few thousandths inch. Or replace it with one the right size.
If the shellholder's hard against the bottom of the die when the ram's at the top of its stroke, that full length sizes the fired case head to shoulder distance as small as possible with that die and that shell holder. Normally, it's about mid point in SAAMI spec dimensions for that measurement on new cases. Such sized cases should fit all chambers with ease.
You are if there's no light showing between the die's bottom and the shell holder's top when the ram's at the top of its stroke.
No, you're correct.
But wait; there's a solution.
Every once in a great while, someone ends up with full length sizing die whose headspace is a bit longer than maximum. And that's coupled with a shell holder whose height is a bit higher than the .125" spec. Their rifle's chamber headspace is a couple thousandths short of minimum specs for headspace. Cases full length sized in that die will be hard to chamber, if they can be at all.
The solution is to reduce the die's headspace so fired case shoulders will be set back further. Grind off a few thousandths inch off the bottom of the die. Or, grind off a few thousandths off the top of the shell holder then mark it for use with that die only. I'd grind off the bottom of the die so the shell holder can be used normally with other cartridges.
Measure the shell holder's top edge to the bottom where the case head rests with a caliper. If it's more than .126" (typical industry limit), grind if off .002" If it's .126" or less, grind off the die's bottom a few thousandths inch. Or replace it with one the right size.
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Woodworker74
Member
Thank you for the replies. Sounds like I've got a lot of measuring and fine tuning to do. I think of all things reloading, headspace is one of the hardest for me to feel confident about. It sounds like I need to invest in a headspace gauge and really get a better feel for what I'm dealing with.
Andrew- yes, that does make sense. Though I'll probably get some crap for it, I am using a Lee Classic press that does not cam over. I am going to experiment with annealing the cases, as well as utilizing the info from Bart B. and Walkalong.
On a possibly related note, I have what may be a dumb question, but what the heck. I reload for 9mm, .223, .308 and .300 WSM. Both my WSM and .223 cartridges fit into a Wilson case gauge AFTER they are fired. My .308 cases do not. Is this normal, or possibly an indicator of an oversize chamber? Other possibilities? Thanks again for all the info and as soon as I have time, I'll be putting it to good use.
Andrew- yes, that does make sense. Though I'll probably get some crap for it, I am using a Lee Classic press that does not cam over. I am going to experiment with annealing the cases, as well as utilizing the info from Bart B. and Walkalong.
On a possibly related note, I have what may be a dumb question, but what the heck. I reload for 9mm, .223, .308 and .300 WSM. Both my WSM and .223 cartridges fit into a Wilson case gauge AFTER they are fired. My .308 cases do not. Is this normal, or possibly an indicator of an oversize chamber? Other possibilities? Thanks again for all the info and as soon as I have time, I'll be putting it to good use.
The instructions that came with my steel 30-06 RCBS dies circa 1970 instructed the user to have the uplifted shell holder lightly press on the base of the sizer die. The idea was to touch the die just enough to be felt and take the spring out of the press's linkage. In this case an RCBS Jr press I still have and use. I've never varied from those instructions and never made the first measurement. If it ain't broke ......
To this day, those old dies, IMR4350, Hornady 180 grain InterLock bullets and my circa 1964 Remington 700 still shoots sub MOA.
To this day, those old dies, IMR4350, Hornady 180 grain InterLock bullets and my circa 1964 Remington 700 still shoots sub MOA.
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