Question Full size or Neck size brass for Accuracy ?

[Tim Singleton]

Not sure how I offended you ole freak!? I am just trying to get my arms around the above consensus that after all these years fl sizing is more accuracy inducing than neck sizing which I started in the early 90s! Anyway, I guess I am just confused! No, I am not trolling and do not want to waste anyone's time! I guess it will be best to just read and not ask questions! Thanks guys! Tom

I think it would all depend upon what is acceptable accuracy and acceptable case life.
If all of your shooting has yielded acceptable results why change anything?

For some of us that load at higher pressures neck sizing is not an option at all. That is where a minimum amount of FL sizing is required. If you size to much as with the standard die setup instructions coomnly give. Then the cases are over sized accuracy suffers and case life is shortened

Back to the beginning if what you've been doing works for you why change anything

 

[Tim Singleton]

Not sure how I offended you ole freak!? I am just trying to get my arms around the above consensus that after all these years fl sizing is more accuracy inducing than neck sizing which I started in the early 90s! Anyway, I guess I am just confused! No, I am not trolling and do not want to waste anyone's time! I guess it will be best to just read and not ask questions! Thanks guys! Tom

I think it would all depend upon what is acceptable accuracy and acceptable case life.
If all of your shooting has yielded acceptable results why change anything?

For some of us that load at higher pressures neck sizing is not an option at all. That is where a minimum amount of FL sizing is required. If you size to much as with the standard die setup instructions coomnly give. Then the cases are over sized accuracy suffers and case life is shortened

Back to the beginning if what you've been doing works for you why change anything

After reading this a couple times. I think Wilbur has rubbed off on me

 

[LHSmith]

Not sure how I offended you ole freak!? I am just trying to get my arms around the above consensus that after all these years fl sizing is more accuracy inducing than neck sizing which I started in the early 90s! Anyway, I guess I am just confused! No, I am not trolling and do not want to waste anyone's time! I guess it will be best to just read and not ask questions! Thanks guys! Tom

FLS 'ing EVERYTIME for best accuracy evolved from Competition Benchrest. Most competitive BR cartridges are pushed hard- simply because that is where the very best accuracy is achieved and neck sizing only will produce a round that chambers with difficulty....that in- turn upsets the bags in the rest which causes one to have to navigate the reticle back to POA -loosing precious seconds adjusting sights instead of shooting in a desired condition (favorable wind, light, and mirage that the shooter has had success in).The rests permitted in Short Range BR do not allow true return to battery due to fact the stock must have a slope towards the heel, but in a well designed stock/ rest set-up the movement required to re-aim after recoil is minimal. BR rifles worthy of competition are accurate enough to show small differences in shoulder bump, and to extract the last bit of accuracy from them, competitors might adjust their bump by 0.0005" on cases they "feel" are causing slight interference when closing the bolt.
Neck sizing will work fine for other types of shooting, but book maximum high pressure loads may cause problems in bolt operation, and excessive lug wear in the long term.

 

['Freak]

Not sure how I offended you ole freak!? I am just trying to get my arms around the above consensus that after all these years fl sizing is more accuracy inducing than neck sizing which I started in the early 90s! Anyway, I guess I am just confused! No, I am not trolling and do not want to waste anyone's time! I guess it will be best to just read and not ask questions! Thanks guys! Tom

tcr1146 – Howdy, pardon again, mean it this time. Pick up or order your copies of these two books:

“Handloading for Competition” by Glen D. Zediker

“The Book of Rifle Accuracy” by Tony Boyer

Both are most excellent reading for any serious rifle shooter. Not everything will apply to your circumstances but both will help you to figure out what does. Neither is a book you’ll read only once and then forget about it.

Later,
‘Freak

 

[dmoran]

If were loading much at all in the direction of upper limits, sizing will become an almost certainty at some point (cycle).
To make our ammo capable of performing exactly the same for every shot, we have to prepare our handloads exactly the same every time -IME

Would we expect 2 different bullets to perform exactly the same?... no... that's why we load all from the same box (lot).
Would we expect 2 separate powders charges to perform exactly the same?... no... that's we make our charges the same weight.
Would we expect 2 different neck tensions to perform exactly the same?... no... that's why we prep our necks all the same.
Would we expect 2 different brass dimensions to perform the same?.... I don't, and is why I re-size with the same procedure, to common dimensions every time, and for every cycle.

Neck sizing only, only works if we never have a need to re-size anything but the neck .
If we have to break routine of neck sizing only, and size any part of the brass at any point/cycle, our ammo is not the same and can not be expected to have the same potentials. To make our ammo the same every time, every effecting step and procedure, has to be repeated every time. Or is how I look at it all and is in part why I F/L-size every time.
Donovan

 

[BoydAllen]

I think that something needs to be pointed out. Most shooters have no experience with dies that are closely matched to the chambers that they are used with, and for that reason, when they discuss the relative merits of neck and FL sizing, they really do not understand what is being said.

A lot of shooters still equate FL sizing with one piece dies that over size necks, so that when expanders are pulled through them, that necks are cocked, guaranteeing crooked ammunition. These same dies are often made to produce case body dimensions that are at SAAMI minimum for loaded ammunition, with the result that when they are used on brass that has been fired in generously dimensioned factory chambers they dramatically over size. Dies that are made to match the chambers that they are to be used with, have none of these issues.

 

[K22]

I used to think I knew reloading but obviously a babe in the woods. For example, the guy above says "bump the shoulder" .001 to .002"?! Just how do I know how to do that?! My full length Redding deluxe die set calls for running the ram all the way to the top, turn the die down to touch the shell holder and then drop the ram and turn the fl die 1/8 to 1/4 turn deeper! Explain how any of that gets me a .001 shoulder bump?! Thanks, Tom

You will need a means to measure the shoulder set back from a fire case from that was fired in the specific rifle that you are reloading for. The Hornady Head Space Tool works well for this purpose. I've found that most manufacturer's instructions result in over sizing the case. There's a manual method to approximate this procedure but I prefer to measure the set back for better precision and adjust for changes that may occur as the case is repeatedly sized.

F/L sizing with the modest shoulder set back will also produce reliable functionality which is critically important if you are a hunter.

You can take this whole process to extremes if that's you're game but to produce safe, reliable and accurate reloads is not rocket science. It depends on your accuracy standards and the amount of time and expense you are willing to commit to squeeze a few .01" tighter groups which may be important if you are a competitive target shooter or if that is your game.

Like many I started reloading in the late 60's and was told that neck sizing produces the most accurate reloads and longest case life. However I soon learned that after repeated neck sizing the case were hard to chamber. Years ago, at the advice of a bench rest shooter, I abandoned neck sizing and began full sizing with a slight shoulder bump. What I discovered was that I experienced no loss in case life, accuracy was slightly better*, and I never had to worry about functionality.

* not sure why - maybe because of less run out?

Like some have already said, you do need an accurate rifle to get the most of any reloads no matter how precise they are constructed.

I do not claim to be an "expert" but for me full sizing with modest shoulder set back method works extremely well for me but I'm not a bench rest shooter, just a long range varmint and predator hunter. My accuracy standards for my varmint and predator rifles / reloads are 1/2 moa. Some of my rifles have custom barrels while other have factory barrels. I use plain old RCBS two die sets, F/L and seater. My neck sizing dies are used as paper weights.

Hope this doesn't upset too many experts.

 

[Dusty Stevens]

You dont need any fancy gauges to determine shoulder bump just remove your firing pin and try it in the chamber. Keep screwing the die down til you feel the case right as the bolt hits the bottom.

 

[tcr1146]

thanks for all the additional responses and patience! As ole freak suggested, I will get one of the books and probably Boyer's! Thanks and I will continue to follow this! Tom

 

[BoydAllen]

Dusty,
This time I have to disagree. Your method is predicated on the idea that the die is small enough so that shoulder bump is not excessive at the point where the feel is what you are looking for. I have seen examples where is was not, particularly with custom chambers. Friends had high quality, slow twist, 6BR varmint rifles built and when I told them that they should sent brass to Harrell's with a die order, they smiled and bought the prettier Redding dies that they were familiar with. After that, they discovered that the Redding dies would not size the bases of their fired cases unless they were set to bump shoulders more than they wanted.This was not the fault of Redding, but rather the result of chamber dimensions from custom reamers that their smiths had used. They ended up doing what I had suggested in the first place, and that solved their problem. I see the advice to use the bolt as a gauge all the time, and if you know that your die is small enough for your chamber it can be useful, but when giving advice on the internet, we cannot know what the fit is can we?

 

[amlevin]

I think that the question needs to be narrowed some. Is F/L sizing better than Neck Sizing in a Factory chamber? Is it better in a Custom Chamber.

There are a lot of people that are F/L sizing for nice tight custom chambers that had reamers ground to fit their FL sized cases. There are also those who have factory chambers, or chambers cut with off the shelf reamers and use custom dies made specifically for those chambers.


Then there are those who merely neck size and achieve great accuracy.

To which group does this question really apply?

Not sure I understand the question or the difference. When I consider the custom rifles I have it seems my custom rifles with special reamer are only tighter necks, rest of dimensions a the same and the neck is controlled by the bushing when I size so don't see the difference. What am I missing? I do understand statements about better accuracy with the full size die.

There are numerous reamers that have manipulated the dimensions of the chamber other than just making the neck area tighter. Some reamers also reduce the dimensions for the remainder of the case to SAAMI minimums. I have one rifle chambered with a reamer that has reduced the body taper to a minimum, just enough to allow for case extraction. The chamber diameter near the case head is only a thou or two greater than the case head yet the shoulder diameter is at SAAMI max. A case that is F/L sized holds 1.5 gr less than a fire-formed neck sized only case.

 

[Brians356]

I used to think I knew reloading but obviously a babe in the woods. For example, the guy above says "bump the shoulder" .001 to .002"?! Just how do I know how to do that?! My full length Redding deluxe die set calls for running the ram all the way to the top, turn the die down to touch the shell holder and then drop the ram and turn the fl die 1/8 to 1/4 turn deeper! Explain how any of that gets me a .001 shoulder bump?! Thanks, Tom

A) You need to be able to measure the distance from case base to the datum line on the shoulder, both on a fired case and after sizing the body, to determine the shoulder setback. The Hornady Lock-N-Load Headspace Gauge system (referenced elsewhere in this thread) is the most common way to do this.

B) You need to control the body sizing (and shoulder setback), and the best way I know of is to use the Redding Competition Shell Holder set.

Go to a vendor like brownells.com and download the instructions for these two products, and all will be revealed.

 

[Eric Leonard]

start your fl die screwed out and size your brass,,turn your die down 1/16th turn at a time untill you can chamber a round freely,,it is that simple to me,,

when I size my brass I like to hold the ram down for a 5 count to give the brass time to hold shape,,I used to just run it down and back up and got erratic results,,when I started holding the 5 count the brass came out lots more the same,,hardly ever load a case that is harder to load than another,,and we all know that round that is harder to load will hit high,,least for me it seems,,

 

[Brians356]

start your fl die screwed out and size your brass,,turn your die down 1/16th turn at a time untill you can chamber a round freely

Yes, but every time you resize those cases again, you need to start over with the loose die and the trial and error. With the indexed shell holders, you find the one that sets the shoulder where you want it, with the press cammed over against the die bottom. Then simply select that same shell holder the next time.

 

[BoydAllen]

There are any number of ways to adjust a die, the main thing is to have the tools to measure how much shoulders are being pushed back during sizing. A single turn of a die makes an adjustment of a bit over .071", so a sixteenth of a turn amounts to an adjustment of a little over .004". I try to limit shoulder bump to less than .002, and use a case that has been fired till tight as a reference. If I only have once fired brass to work with, and since it generally has plenty of clearance left at the shoulder, I set my dies to replicate the shoulder to head dimension (actually datum to head) of the fired brass, being sure to reseat the fired primer well below flush before measuring the fired case.

One way that I have handled the preservation of die adjustment for my non-benchrest applications is to convert my Rockchucker to Lock-n-Load. That way the die setting is preserved when the die is locked to the adapter. This works for seating dies as well. For my 6PPC, I use a PMA Tool Micro Die Adjuster.
https://www.youtube.com/watch?v=iR7iixACxR4
(I do not sell them, or profit from them, and this was my first and only attempt at making a demonstration video.)

 

[Travelor]

Way back in time, maybe 55 years or so, the NRA ran a accuracy test with a factory 30-06. They shot the same gun with the same load both full length resized and neck sized. The full length sized ammo shot better. Results were published in the American Rifleman magazine.

I believe the conclusion was that the factory chamber/ammo fit caused the cases to expand unevenly (laying at the bottom of the chamber when fired) and the next load sized only with the neck sized ammo was not aligning the bullet to the barrel as well as full length sized ammo.

Wish I had kept all my magazines, but then I would have to live in the backyard as the house would be full of magazines.

 

[amlevin]

There are any number of ways to adjust a die, the main thing is to have the tools to measure how much shoulders are being pushed back during sizing. A single turn of a die makes an adjustment of a bit over .071", so a sixteenth of a turn amounts to an adjustment of a little over .004". I try to limit shoulder bump to less than .002, and use a case that has been fired till tight as a reference. If I only have once fired brass to work with, and since it generally has plenty of clearance left at the shoulder, I set my dies to replicate the shoulder to head dimension (actually datum to head) of the fired brass, being sure to reseat the fired primer well below flush before measuring the fired case.

One way that I have handled the preservation of die adjustment for my non-benchrest applications is to convert my Rockchucker to Lock-n-Load. That way the die setting is preserved when the die is locked to the adapter. This works for seating dies as well. For my 6PPC, I use a PMA Tool Micro Die Adjuster.
https://www.youtube.com/watch?v=iR7iixACxR4
(I do not sell them, or profit from them, and this was my first and only attempt at making a demonstration video.)

Your post makes a great argument for the Redding Competition Shell Holders. Fixed adjustments of .002" increments and a true "Dead Lenth" system with the die locked tight against the shell holder for each and every case.

The PMA adjuster is OK but varying sizing pressures COULD affect the outcomes for a string of cases.

Not a chance using the Redding shell holders.

 

[amlevin]

Way back in time, maybe 55 years or so, the NRA ran a accuracy test with a factory 30-06. They shot the same gun with the same load both full length resized and neck sized. The full length sized ammo shot better. Results were published in the American Rifleman magazine.

I believe the conclusion was that the factory chamber/ammo fit caused the cases to expand unevenly (laying at the bottom of the chamber when fired) and the next load sized only with the neck sized ammo was not aligning the bullet to the barrel as well as full length sized ammo.

Wish I had kept all my magazines, but then I would have to live in the backyard as the house would be full of magazines.

I'm sure the article was interesting but how can you draw a conclusion by running a test with a single firearm?

Things have changed greatly in 55 years, especially in the consistency of barrel construction and machining. I'm sure a lot more of todays "factory rifles" have chambers that are cut more concentric to the bore than in years past. Especially those that have the chamber and rifling created in a single step using a one piece mandrel (CHF barrels).

 

[LHSmith]

The PMA adjuster is OK but varying sizing pressures COULD affect the outcomes for a string of cases.

Not a chance using the Redding shell holders.

I don't follow this statement. The manner in which the press ram is operated must be maintained no matter what method is used......shims, JLC die adjuster, PMA micro, or Redding Comp. S/H's.

 

[BoydAllen]

There is a variable in the process that solid contact between shell holder and die addresses, linkage slop and or compression. The height that the ram comes to at full stroke can vary slightly , depending on differences in pressure required to size a case. This can be because of differences in the cases, as well as how each case is lubed. The Redding Competition shell holder sets address this by allowing the user to use various heights of shell holders so that when dies are set correctly for shoulder bump, that the press toggles slightly against the die which makes the height that the ram rises to more uniform.