Huntnful
Well-Known Member
The sizing of the case body, bumping the shoulder AND squeezing the neck back down with the inserted bushing all happen at the same time. Only the 21st century mandrel expansion is a separate process.
-
If you are being asked to change your password, and unsure how to do it, follow these instructions. Click here
Neck Tension Lapua 300prc
- Thread starter LocalJW
- Start date
Help Support Long Range Hunting Forum
QuietTexan
Well-Known Member
No, that's double work that you don't need to do. What you're describing is the process for the Redding set that comes with a body die and a neck die. In that set sizing is split between two dies. Redding mixes and matches dies in various sets that can be confusing sometimes, some sets (the Elite set) some with FL and neck dies that both ultimately size the neck, but give the ability to split into a body-sizing-plus-neck or neck-only process.
For most of my cases I use a Type S Bushing Neck Die (or other brands' equivalent) without a sizing button, then a mandrel, then finally a Competition seater. I decap on a separate die before whatever case cleaning (if any) I do. I avoid FL dies as often as I can.
One thing you'll learn as you get more into using mandrels is that what matters the most isn't just the final dimensions, it's how far the brass moved in total to get there. Using a bushing and mandrel to move inwards 0.0015" and outwards 0.0005" is less total movement than moving in 0.004" and outwards 0.003". The point of using bushings and mandrels is to reduce total overall movement. When you asked what mandrels to get, my answer is "the whole darn set for each caliber" because if you ever use multiple brands/lots of brass you'll end up using more than just one or two mandrels in the set.
I use neck-only dies to size cases after the first few firings until the case will not rechamber in the rifle without effort, then I set up the sizing die. Nothing makes me cringe more than someone saying they're "bumping shoulders" on "once-fired brass", at that point you might as well use an FL die and squeeze the rest of the life out of the case.
Throw away the instructions that come with whatever sizing die you buy, they're generally useless, especially the FL die instructions based off turning back from shell holder contact. Watch the video at the end of the post on how to do it correctly.
List of Dies:
Standard full length (FL) sizing die - does body, shoulder, neck, all at once. Uses a button to expand the neck inner diameter back to an approximation of the correct size because FL dies typically size cases the most, to the smallest dimensions, to ensure fit in all chambers. Can decap. Don't bother using a mandrel after this die - you have to use the button on the decapping stem to open the case neck back up enough to be useable at all, using a mandrel on top of that is just more work on the brass that you won't see a gain from because the brass is moved so much in and out unless you anneal every time your brass hardness is going to be all over the world. This is the basic die for basic loading, it doesn't have many uses in precision bolt-action reloading.
Type S - Bushing Full Die - does the body and shoulder dimension, but allows you to select a replaceable bushing for outside neck diameter in 0.001" increments. Allows for coarse control of length of neck sized by the bushing, retains the option of using a sizing button to pull back through the neck to set final neck inner diameter. Can decap. Use of the mandrel after sizing with this die replaces the use of the sizing button and requires you to get the Redding decapping pin holder that is smaller than neck inner diameter.
Type S - Bushing Neck Die - uses a bushing and optional sizing button to only resize the neck, does not resize the case body or the shoulders. Only allows for coarse adjustment of neck sizing length using the bushing stem. Can decap. Use of the mandrel after sizing with this die replaces the use of the sizing button and requires you to get the Redding decapping pin holder that is smaller than neck inner diameter.
Competition Bushing Neck Die - same function as the Type S neck bushing die, but adds a micrometer stem to better control length of neck sized, and a sliding inner sleeve to hold the case during the neck sizing operation. Cannot decap. Use of the mandrel after sizing with this die makes the last sizing operation an expansion, so the neck should creep inwards as brass continues to move after exansion. Not using a mandrel after this step results in neck thickness variations being on the inside of the neck and the last sizing operation being inwards, meaning brass creep is outwards.
Body Die - mimics the FL die in how it sizes the case body and shoulder, but does not size the neck at all. Cannot decap. Resized case will not hold a bullet unless the neck is sized in some manner after using this die.
Small Base Body Die - a body die that sizes the lower case smaller than a standard body or FL die, but does not size the neck at all. Cannot decap. Resized case will not hold a bullet unless the neck is sized in some manner after using this die.
Standard Seating Die - uses a coarse adjustment screw to control bullet seating depth.
Competition Seating Die - uses a micrometer to control bullet seating depth, and has a sliding internal sleeve to support to case during the seating operation.
Another common die is the Forster "Bump" Die - this die is capable of resizing case shoulders, but is not designed to resize the case body. Uses bushings to control neck outer diameter.
Last edited:
Heavy recoil rifles may need more neck tension, unless a single shot action.
Autos more then bolt actions.
I use the Redding type S fl bushing die in 243 & 6.5 CM.
The expander that comes with the FL die is used. The bushing sizes the neck just small enough that the expander can be felt on all brass, as the expander slides thru the lubed necks.
Seems to work ok.
Neck tension of .002" works in light recoiling bolt actions.
Autos more then bolt actions.
I use the Redding type S fl bushing die in 243 & 6.5 CM.
The expander that comes with the FL die is used. The bushing sizes the neck just small enough that the expander can be felt on all brass, as the expander slides thru the lubed necks.
Seems to work ok.
Neck tension of .002" works in light recoiling bolt actions.
I used to be in the camp were .002 nk tension was were I basically loaded about everything until the last few years I started testing nk tension and WOW! what an eye opener. These days on my LR hunting stuff I'm anywhere from .003 to .005 nk tension depending on rifle and chamber.
On Lapua, ADG and nk turned brass ive also quit using mandrels or buttons and just use strictly bushings to size nks.
Saying that I have guage pins to make sure the bushings i use are what they say they are because some are not.
Nk tension is one I dont feel shows until you start getting farther out is another reason I dont do load development at 100 unless its just kinda getting a scope on paper and trying to find pressure in a new rifle.
On Lapua, ADG and nk turned brass ive also quit using mandrels or buttons and just use strictly bushings to size nks.
Saying that I have guage pins to make sure the bushings i use are what they say they are because some are not.
Nk tension is one I dont feel shows until you start getting farther out is another reason I dont do load development at 100 unless its just kinda getting a scope on paper and trying to find pressure in a new rifle.
Stretch_TX
Well-Known Member
- Joined
- Aug 28, 2017
- Messages
- 47
Here's another high quality option as far as mandrel pins and the die & collet to use them. They are available in 0.0005" increments.
www.portersprecisionproducts.com
www.portersprecisionproducts.com
www.portersprecisionproducts.com
Once you have the die and appropriate collet for you caliber, the pins are very reasonable.
Starter Sets – Porter's Precision Products
www.portersprecisionproducts.com
Pins – Porter's Precision Products
www.portersprecisionproducts.com
Die Bodies – Porter's Precision Products
www.portersprecisionproducts.com
Once you have the die and appropriate collet for you caliber, the pins are very reasonable.
Stevenstl86
Well-Known Member
Based on a bolt gun with a good chamber. Redding type s with .002-.004 neck tension for bolt guns. Take the mandrel off. There is no need for it, you would just overwork the neck. Firing the round will open the case mouth plenty.
Autoloading rifles could have deformed case mouths needing the mandrel to straiten them out
Sam with panhandle precision had done extensive testing on this. Your cases will last 20x or more if you FL size cases properly for your chamber and not ran at max pressures. Most good nodes are below max or over max anyways. Your primer pockets should be the first to go, becoming loose at the end of their life. You should anneal after every firing but most of us don't and just keep running it because we don't shoot enough. This is where work hardening starts and your neck tension becomes less consistent with no spring back causing splits.
Autoloading rifles could have deformed case mouths needing the mandrel to straiten them out
Sam with panhandle precision had done extensive testing on this. Your cases will last 20x or more if you FL size cases properly for your chamber and not ran at max pressures. Most good nodes are below max or over max anyways. Your primer pockets should be the first to go, becoming loose at the end of their life. You should anneal after every firing but most of us don't and just keep running it because we don't shoot enough. This is where work hardening starts and your neck tension becomes less consistent with no spring back causing splits.
SteveBurton
Formerly 'Jackmonkey'
I generally start with 0.002 neck tension but then play around with 0.003 or 0.004 to see what my rifles like. I use Redding Type S FL dies without the expander and SAC bushings to size the cases. Then I use a 21st Century mandrel to set final neck tension. You can play around with different sized bushings and mandrels to achieve the tension you want without overworking the brass. I also check cases with pin gauges to verify that I actually have the tension I want. I anneal after every firing. Sounds a bit overboard to some but I have seen a big improvement in seating force consistency, SDs and accuracy. Plus I like to tinker.
So I guess why do you use a neck sizer and then run the mandrel? I'm sorry i'm just new to neck tensioning and trying to understand.
Does neck sizers not actually tension neck and the mandrel Returns ut back to final sizing?
entoptics
Well-Known Member
- Joined
- Jan 16, 2018
- Messages
- 881
The idea of the mandrel is that it will reduce run out compared to the sizer button that's in the sizing die, as well as pushing any inconsistencies to the outside of the neck, increasing uniformity of the surface that's gripping the bullet.
If your brass has variable thickness in the neck walls, when you size from the outside (bushing, conventional die), you are making the outside uniform, which means the inside is now accommodating the variation. A mandrel works in the opposite direction (inside uniform, outside variable). The sizer button in the die would do the same thing, but it's thought to not be as consistent/precise as a dedicated mandrel setup. Perhaps because your doing a lot of sizing in a single pass, so all the forces/friction from sizing the body, neck, and shoulder are happening at once so a little variation in press stroke, case lube, etc can add up to less uniform results overall.
LocalJW if you have a ball mic you will see right away why you use both.Even with the best brass the neck will have irregularities in the neck.
My bushing die sets the neck tension to .002 and then I use a 30 cal mandrell from 21st century and it pushes all irregularities to the outside of the neck so it will be a consistant neck tension on each case.
Entopics explained well.I was typing as he was typing but we both said the same thing.Sorry Entopics.
My bushing die sets the neck tension to .002 and then I use a 30 cal mandrell from 21st century and it pushes all irregularities to the outside of the neck so it will be a consistant neck tension on each case.
Entopics explained well.I was typing as he was typing but we both said the same thing.Sorry Entopics.
Last edited:
So I guess your steps in reloading is what?
I typically
1) FL size/expander ball and decap with Redding die,
2) then clean in tumbler,
3) then ensure case length, then de bur.
4) Prime
and finally load.
Where would you put running the mandrels and or neck tension bushings? Do you do both?
My goal is to stop using decap and expander ball with FL die.
So just do FL and potential neck bushing and then run a mandrel to run all consistency to outside of neck
I can assure you there's alot of really good shooters that use nothing but bushings.
And im pretty sure Alex Wheeler touched on this subject here before.
Bushing only results don't lie.
Attachments
Personally I use both.The S type dies sets the neck tension but the mandrel pushes the irregularities to the outside of the neck so you have better purchase on the inside.
Make's sense? I cut my groups way down using this step.
On my 308,30-06 I use .002 neck tension but on 300 win mag I use .003 and on 300 weatherby mag I do something altogether different.
You do as your rifle suggests.Try .002 and shoot,I tried 3 different mandrels before settling the ones I mentioned.
Try no mandrel and see what your rifle says,Sherm is an experienced shooter and knows more than I do,your rifle will make the final determination.
Make's sense? I cut my groups way down using this step.
On my 308,30-06 I use .002 neck tension but on 300 win mag I use .003 and on 300 weatherby mag I do something altogether different.
You do as your rifle suggests.Try .002 and shoot,I tried 3 different mandrels before settling the ones I mentioned.
Try no mandrel and see what your rifle says,Sherm is an experienced shooter and knows more than I do,your rifle will make the final determination.
I dont like running anything down the inside of my necks on my brass other than a brush right before powder and bullet, I dont want any carbon upset that a nylon brush won't disturb.
My suggestion is test mandrel vrs non- mandrel and come to your conclusions on your test. Again I dont think you would see a difference if you just do it at 100.
The 6.5x06AI target was with turned Lapua 06 brass thats .015 short of max length.
The 28 Noz is unturned brass
My suggestion is test mandrel vrs non- mandrel and come to your conclusions on your test. Again I dont think you would see a difference if you just do it at 100.
The 6.5x06AI target was with turned Lapua 06 brass thats .015 short of max length.
The 28 Noz is unturned brass
