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Inconsistent Neck Tension.


chaz

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Hi folks,

I've got a problem. New Tikka TAC 1 rifle, in 6.5 Creedmoor, broken in 'properly' with around 70 rounds. New Lapua small primer brass, (FL Sized before using on first firings) Developing new loads. 139 Lapua Scenar, 130 Sierra TMK, and 143 Hornady ELD-X. All Various loads with Viht N150 powder, and Federal Gold small primers.

Had a few promising groups at the upper end of the powder range on first firings.....

Dies used were all Hornady Custom.... Brass then decapped, Sonic cleaned, and left to dry on a hot lounge radiator. Then Run through my full length die, (minus the complete sizing rod) due to the shoulders coming forward. (A first for me). Rightly or wrongly, after bumping the shoulders back with the FL die, minus the rod and expander, i then neck sized the brass.

Priming went fine, nice consistent fit with all, (around 44 odd). Filled the cases with various loads of N150, as before. I then loaded around 16 cases with 130 TMK's. And around 28 with 143 ELD-X heads. While seating the TMK's, they were seated at around 80% of the whole neck gripping surface. As for the 143 ELD-X, they were fully seated in the neck surface.

However, the neck tensions were all over the place! Very lightly held some times, Then a decent amount. More so, with the ELD-X's, compared to the TMK's, but not far off. And i did load a lot more ELD-X rounds. The only brass that gave consistent tension were the 8 pieces of new virgin brass i used for a couple of loads of 4 rounds.

Same dies, same press, shell holder, the lot! So where am i going wrong? Just to add there were no compressed loads. In fact nowhere close.....  I've used my sonic cleaner for used brass given to me. And i use it for my Lapua .223 brass. Both with no problems like this.

It makes me wonder if its even worth trying the new loads...???

I could really do with some constructive advice here folks....:(

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Quit with the neck sizing - just FL size.

In a previous post I made the point that neck sizing pushes all the inconsistencies of the brass inwards, to the inside neck diameter, which will affect neck tension/grip on the bullets.

I'd suggest getting yourself a Sinclair (or other) Expander Mandrel die. Using the Expander Mandrel AFTER you FL size will open the neck to about 0.02 undersize and it'll also push all brass inconsistencies to the outside of the neck. This will all help with improving neck tension.

BTW, how are your loads shooting/grouping?

Also what neck size bushing are you using? Bear in mind not all bullets by different manufacturers are exactly the same diameter. You will likely need a series of different bushings to increase/decrease the neck tension to suit your bullet/case combo. Simplest way to determine this is by using your calipers to measure a bullet (do so for each type of bullet you have), then measure the thickness of the brass at the neck mouth. Take the brass thickness measurement, times it by two (because you'll have the brass on the other side of the bullet) and add this number to the diameter of your chosen bullet. Now subtract about 0.02" (for desired neck tension). The number given should equate to a bushing size/diameter. I bet you'll get different numbers for different bullets. 

Again, I still believe you get the best results from giving up neck sizing! Just my opinion.

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Thanks for replying.

I'll answer things in order.

So FL size using my dies expander, then after this, use the Expander Mandrel die then too?

The Scenar 139's were the easiest and quickest to do. I haven't got my data book near me, but the Scenars are sub half moa with 39 grains of N150. I don't recall off-hand what the bullet depth, and the fps was..

The 130 TMK's were not too bad. Easily well under sub moa within the first batch of loads. No further data at the mo though.

The 143 ELD-X's were/are the hardest, which surprised me, as i use mostly V-Max and A-Max, in my .223R and find them quite easy to sort a load for. So the verdict is still out on these at the moment, bar maybe sub moa, just...

As regarding a bushing die, i'm not using one. Just standard dies. Always have... Albeit, with hindsight, i knew i was going to use the 6.5CM for distance, so perhaps i should have bought more wisely at the time.... I appreciate same calibre bullets of different makes come with slightly different diameters. I should have clarified i mean't of the same make. 

Spooky you mention measuring neck tension as I've been reading (back up) on how to do it, along with bushing dies, and as of this morning watching some videos on using mandrels. It was probably obvious to everyone else who watched it, but i wasn't sure if you left the original dies expander in or not, and the 2 videos i saw weren't clear enough to tell which was the case...:blush: 

Apologies, another dim question.. When you use a bushing die, do you draw the brass back over the standard expander? And if so, does that not defeat the object of various bushing die sizes. I obviously need (and will) watch more videos.......    My understanding was that bushings came with corresponding expanders?. Like the new Whidden's 'Click die'.??

And lastly, has it ever been proven that there's no obvious winner when it comes to accuracy and case life, when using a NS or FL sizing die? There seems to be a lot for both sides? 

Cheers

Chaz.  

 

 

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Hi Chaz

loads of questions there ? I'll do my best to answer.

1. I'd just not bother with the expander button in your FL die. IMO I've never had a good experience with one. Simply dissemble the die, unscrew the expander (leaving the decapping pin in place for primers). FL the brass (without expander) then use your Sinclair Expander Mandrel Die (costs about £20)

2.  You say you aren't using bushings but in your first post you state you neck size the brass after you FL size. How are you neck sizing without using a neck sizing die with bushing? Have you dissasembled the neck die to see what bushing is in there? If you do find a bushing, it should have a number marked on it. This tells you the inside diameter. You can buy extra bushings and simply order 2-3, the size you want (per my previous mesuring instructions) and one size above and below. You then have a number of possible tensions to try. BUT...tbh, I just wouldn't bother neck sizing. Use the FL die then the expander mandrel die.

3. So what happens with a sizing die with internal expander is the brass enters the die, the expander forces the neck open, then the neck is reduced (either with bushing of neck sizing or a 'standard' amount if FL sizing) and primer removed. Drawing the brass out now pulls the expander back through the neck opening it up again. But it's this pulling which can both stretch the brass but also get things out of whack. Using a dedicated Expander Mandrel die, the brass has already been sized and neck diameter reduced. As the brass enters the Expander Mandrel, the calibre specific Mandrel opens the neck. Drawing the brass out of the Expander Mandrel doesn't do any further sizing or pulling on the brass as that was done on the 'down' stroke of the press. Expander Mandrels also use a floating mandrel, so it self centres which aids a more concentric sizing operation.

using a neck sizing die together with an expander mandrel doesn't make sense. If you think about what the neck die does (reduce neck diameter by a predetermined amount using the bushing size of your choice) you then just open it up again according to the diameter of the calibre specific Expander Mandrel die. Which is why I think it's best to simply ditch the neck sizing die & bushings and just use a FL die and Expander Mandrel die.

4. If you look at most shooting disciplines, you'll note most people FL size. If you're running a competition, F class, PRS etc, you want your cases to feed easily without getting stuck. NS you can't guarantee that. With FL you can. Some people will say NS your ur brass is the size of your chamber. True. But when the brass grows and expands with successive firing, you've got to FL size it anyway. Having tight fitting brass one moment then looser brass the next you can't ever know if shooting the looser fitting brass will cause a change in shot. Whereas if you FL size, you're bumping shoulder only a tiny amount but all your brass is consistently at always the same size. You can now guarantee shot to shot consistentcy because your brass will always be the same dimension. 

Also with FL sizing, as you're only bumping the shoulder a very small amount each time it's not really working your brass. Using the expander in your die (pushing through neck, sizing neck, then pulling Expander back through again) actually works the brass more!

Admittedly, firing and sizing brass does 'work harden it' - meaning it looses its elasticity, becoming brittle and easy to break/split. Annealing is your friend here and softens the brass again, prolonging its life. This is another advanced step which probably won't be of benefit to you yet but may be something you wish to consider for the future.

A lot to chew over, but for simplicity, I'd bin the neck die and only FL size then use Expander Mandrel.

HTH

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Oh and to fine tune your loads, you'll need to play around with seating depth.

use the OCW method (if you aren't already) to find a nice consistent powder charge node and then play with seating (bullet deeper or shallower in the case) to find what works best. You may find bullets like to be jammed into your lands or jumped into them. You may also find you need to try a different powder or even primer, so don't discount these possibilities.

As ever, good luck & happy shooting!

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Thanks for the reply HTH. 

Before i read more indepth and put a reply to your advice. I'm quite surprised nobody else has bothered to chip in....

Anyhow, and have a good read of your help and advice.

Chaz.

 

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I post that and at the same time JCS replies. Thanks JCS. Whats your reasoning for the focusing on one bullet and one powder? Consistency?

Cheers.

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I would not complicate things by looking to use different sizing dies for different jobs just yet or messing about with trying different loads except perhaps for verifying your current ones using OCW + chronograph.  I can manage single figure ES using simple Lee FL dies.  As Catch-22 says,  use the Hornady FL die as designed, with the expander back in place and then I would recommend (if you don't already have one) use a Lee factory crimp die once your rounds are seated.  I've found that consistently improves uniformity of neck tension.  You don't need much of a crimp either.  Mine is set less than half way of the available crimp tension.  I used this recently resulting in the tightest ES figures that I've ever achieved.

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1 hour ago, chaz said:

I post that and at the same time JCS replies. Thanks JCS. Whats your reasoning for the focusing on one bullet and one powder? Consistency?

Cheers.

Reloading is about all constituency and simplicity. Focus on one bullet and develop a load for it. It may be you need to change powder, but work at one bullet until you are happy with the results, then pursue developing a load for a second bullet. Keep good records while you are going along.

Good luck.

JCS

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2 hours ago, chaz said:

Thanks for the reply HTH. 

Before i read more indepth and put a reply to your advice. I'm quite surprised nobody else has bothered to chip in....

Anyhow, and have a good read of your help and advice.

Chaz.

 

Chaz 

re. ‘Not bothering’ some of us have day jobs ?

re consistency, as others have said a change of technique or tools would improve things.

personnaly I anneal, FL size (to a degree) using a neck bushing that just sized enough so an expander does some work, this is checked using a pin gauge that can be ordered with the expander, I use .002” neck tension on a 6.5x47 which seems to work 

I did hand seat but went back to a Co-ax press.

very consistent neck tension and performance of the rifle.

brgds T

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This will make you wince ,,,,just out of interest I removed the decapping pin assembly from a RCBS 6.5x47 FL die and just run a case up and out of the die,,,,,,this die squeezed the neck down to .278 !! from its fired size of .293. If the sizing button was then drawn through it would then rip it at least 10 thou back out again !!! that's a lot of working the necks and there are far better ways of doing it. I bet some people don't even lube the necks making it an even more painful process ,,,,,,,recognise yourself? haha.

I personally use a process to partial FL size and neck size at same time using bushing dies etc and is very gentle on precious neck turned brass or any brass come to that.

There are other methods also mentioned above and also work well.

Laurie mentioned a cheap trick in some other post and is also a method I use with my 223 and thats to partial FL size with a redding body die and appropriate shell holder and then neck size with a lee neck sizer.This method really works well,,,,if more neck tension is required then the decapping pin/mandrel can easily be spun down in a drill with some emery to get the exact amount of tension you are looking for although lee have it pretty good to start with.

I really don't know why die makers make their dies squeeze the hell out of necks,,,it is so excessive,,,,,,,,I tried a forster FL die as well ,,,same thing!!,,,,this could be where/why variances in resultant neck tension are being felt,,,,?,,,,,,,,,,,,,,,,,O

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Thanks for the input folks. My comment wasn't mean't to offend, I forget most people have busier lives than me... I have plenty of 'keyboard' time as i'm partly disabled and forums take my mind off the pain sometimes. No sob story just explaining. :)

I've been reloading for around 5 years, so have done most things, and got there by advice from forums and trial and error. I found the .22 Hornet and .223R reloading pretty easy going to be honest. The 6.5CM is turning out not so easy i suppose.

I've previously used mostly new Lapua brass, and some PPU cases from cheap ammo I've bought to try new things out before doing the same with my best brass.

I've always bought a standard Hornady Custom 3 die set, consisting of standard non bushing FL and NS dies, using the decapping rod and expander. Along with a seating die with the A-Max seating stems where needed and a Micrometer adjuster.

I've done the same with the 6.5CM, but things are not going so easy. I guess JCS has a point by me initially trying 3 different types of bullets, albeit everything else was the same. As I've said the Scenar 139's were a quick job to find a good load thankfully.... 

I suppose in essence i'm just puzzled how new Lapua brass can have such inconsistent neck tension when it's only on it's second firing, and using new dies. Albeit standard basic dies. Which i stripped and cleaned the storage rust preventive oil off before setting them up, and all looked well made, to the best of my knowledge. The issue was after bumping the shoulders back with my FL die, with the decapping rod and expander removed. Then neck sizing with my non bushing standard NS die. 

I was a believer that neck sizing once fire formed was the way to go, then FL size when needed, and anneal after 5 loads using Tempilaq. And start again. I've read that sonic cleaning can have an effect on brass, but couldn't find any info that said why.

Another good point stated by Catch-22 regarding my method of reloading, was when it got to the stage where i needed to FL size my brass. I'd always have to waste 3 or 4 rounds, making sure my point of aim was still on. I could of just done it the once, but peace of mind made me do it after every FL sizing, as i hate the thought of a poorly placed shot causing an animal to suffer. So FL sizing is better than neck sizing in that respect. And when added to the point about using an expander mandrel die to size the neck, it seems a better more consistent way of resizing my brass. 

VarmLR, I'm not keen on crimping, just a personal thing really.... But i have used a Lee factory crimp die before, and didn't get on well with it. Although that was when i first started reloading, so it was probably down to my inexperience... I use a Chronograph when doing load development though, and always right everything down in my pad. Although i must admit ES is quite new to me, so I've only just started recording it.

I'm interested to see if others use this method, as it sounds like a lot of serious target shooters size their brass this way. According to You-tube anyhow....  And as i had to bump the shoulders of my Lapua brass on it's second firing, it seems a better way to go...??

I'll have a mooch on Accurate Shooter and see what else i can find. It seems a great source of true info...

Cheers

Chaz.

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There is one variable not raised in reply here (well at least my skim reading suggests so).

I immediately spotted the brass had been sonically cleaned and I didn't spot where inside neck lube had been used at any stage. When brass is so squeaky dry clean from this treatment, it can be very grippy on projectiles.

I'd be tempted to use an expander mandrel with the neck dipped in graphite (~ Imperial dry lube) after the cases had been sized. This will leave a residual lubrication in the neck and should give more consistent true neck tension.

Just a thought..

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Cheers Chris. You're spot on. I just found a review of sonic cleaners on the Accurate Shooting forum. And that's what was said on there too. I'm just sorting out some Imperial dry neck lube. Got to be worth a try. And they do come out very 'squeaky' indeed! I'll also be buying an expander mandrel. Just not sure whether to buy the 001" mandrel, or the neck turner mandrel (states matches the same in reviews) but is 002". In fact probably best to get both...

Cheers

Chaz. 

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On 17/04/2018 at 10:28 AM, chaz said:

Thanks for the reply HTH. 

Before i read more indepth and put a reply to your advice. I'm quite surprised nobody else has bothered to chip in....

Anyhow, and have a good read of your help and advice.

Chaz.

 

But many of us have bothered to chip in and offer advice Chaz puzzled-smiley-emoticon.gif

I would never lube the necks, even dry lube them. The inside of my brass necks are always cleaned (U/S) following sizing and trimming.

I still think me old mucker that you may be over complicating the sizing process and adding stages can just add to inconsistencies if not careful. Keep it simple, forget neck sizing and just FL size after each firing.  Use a Lee factory crimp die for a very slight crimp and you should find that you help with neck tension uniforming.  My most consistent loads have been achieved this way.  Everyone has their own methods but when it comes to 6.5 loads, you may find that primer pockets come loose long before you ever have issues with over-working of brass, especially if you already anneal.  I think it's questionable ( in terms of all the evidence presented) that FL sizing reduces life of brass by much, if anything.  Neck sizing also means at some point having to FL size so capacities change and loads are arguably less consistent, but FL sizing ensures, as much as possible anyway, the most consistent case capacities.  Just my humble opinion...others will have what works for them.

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VarmLR.  Good to hear from you. Hope things are going well with your Tikka TAC1 6.5CM. But why the silly ott emoji at the start of the post? Then some constructive advice in the middle. Then the 'Just my humble opinion'  at the end? I believe that's known as a '**** sandwich'....

I'm not known for being the sensitive type.... But i had to mention it, as it made me smile, and reminded me of some of the less than inspiring management in my last job.

Anyway, I mentioned the lack of 'different' members responses nearly 24 hours after my initial posting. And exactly the same time i got a response from a second person. That being JCS. (Thanks JCS) I also explained my reasons for having 'lots of keyboard' time. And as you may appreciate, the more advice the better. Different perspectives and the like...

However all constructive advice is much appreciated as per my original post.

Cheers

Chaz.

 

 

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My forster  benchrest die gives me 2 thousandths neck tension after the expander ball has been through.take expander ball off and it makes it 6 thousanths neck tension.i know which I prefer

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1 hour ago, No i deer said:

My forster go benchrest die gives me 2 thousandths neck tension after the expander ball has been through.take expander ball off and it makes it 6 thousanths neck tension.i know which I prefer

At least your "benchrest" die works to more acceptable working of the brass ,,,,,,standard dies seem to want to murder necks,,,,,O

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Forster is good stuff though I did have problems with the first 2 dies that got sent back.i feel I am not quite getting the best out of my 6.5x47 and need to spend time fine tuning after seeing the recent ukbra results.there is more accuracy to be had.its a very popular calibre with the br shooters it seems.its holds the 1000yds world record aswell using 139gr scenars apparently.

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So you may or may not have a tight neck chamber. Firing expands the neck to that size whatever it is. Putting the case through the die crushes it down to -6 thou and the expander expands it to -2 thou. That seems like a lot of brass working to me?

My experience with 308W: I have been using a Redding comp neck bush die(no expander) & Redding body die to control head space. However I was using an over small bush and then using K&M expanders to get correct tension and hopefully to push irregularities to the outside of the neck. I shoot FTR so have to have std chamber. Firing expands neck to @0.314 inside. Neck bush then takes it down to @0.302 and expander takes it back to 0.306. I have discovered that if you neck bush that much in one go there is no way that the neck runs true even though it is dead true after firing. Yes annealed each firing but so far no way to get them true. Trying to neck size in smaller steps. The jury remains out!

Thinking about it maybe the expander in the die helps straighten it again as it does it on the way out and not the way in?

Sorry this is a bit of a thread hijack but I am interested in peoples findings re this.

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1 hour ago, Webby said:

So you may or may not have a tight neck chamber. Firing expands the neck to that size whatever it is. Putting the case through the die crushes it down to -6 thou and the expander expands it to -2 thou. That seems like a lot of brass working to me?

My experience with 308W: I have been using a Redding comp neck bush die(no expander) & Redding body die to control head space. However I was using an over small bush and then using K&M expanders to get correct tension and hopefully to push irregularities to the outside of the neck. I shoot FTR so have to have std chamber. Firing expands neck to @0.314 inside. Neck bush then takes it down to @0.302 and expander takes it back to 0.306. I have discovered that if you neck bush that much in one go there is no way that the neck runs true even though it is dead true after firing. Yes annealed each firing but so far no way to get them true. Trying to neck size in smaller steps. The jury remains out!

Thinking about it maybe the expander in the die helps straighten it again as it does it on the way out and not the way in?

Sorry this is a bit of a thread hijack but I am interested in peoples findings re this.

To the contrary Webby, I'm also interested in peoples findings, so add what you want. :)  I've never had to deal with body sizing, and poor neck tension before, so i'm keen to have all the constructive feedback i can. 

Just to add, from my limited knowledge on the suspect, 6 thou to 2 thou seems a lot of work on the brass to me too. I've not really paid too much attention to the forces pushed down on the neck while the expander was going in. Although It had also crossed my mind that maybe the expander pulled the necks straight and true on the way out...

Chaz

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8 hours ago, No i deer said:

Forster is good stuff though I did have problems with the first 2 dies that got sent back.i feel I am not quite getting the best out of my 6.5x47 and need to spend time fine tuning after seeing the recent ukbra results.there is more accuracy to be had.its a very popular calibre with the br shooters it seems.its holds the 1000yds world record aswell using 139gr scenars apparently.

Forster is good stuff, although i only have a few items made by them..... I have the 'original' case trimmer, fitted with the 3 in 1 case trimmer, chamfer, and deburring head. It was a pain to set-up, but now set up for my 6.5CM it's a great bit of consistent kit. Perhaps I should have bought Forster dies in the first place...???

I've ordered a Sinclair expander die, mandrels, and graphite type dry inside neck lube from Brownells UK. Which turned out to be a mistake. Although their prices were better than most, and I was silly enough to believe that when a site says items are 'in stock', and see others saying 'back-order', i believed that mean't in stock in the UK. But it doesn't. It means in the USA!! I thought i'd have the items to at least try and sort out my neck tension issues over the weekend. But apparently 'in stock' in a UK suppliers, (according to Brownells UK) means i will have to wait nearly 2 1/2 weeks for delivery!! I did question this by email, and got the old 'terms and conditions' reply. I won't make the mistake of ordering off them again...

Maybe my Lee collet neck sizing die will sort things out. At least that was a genuine UK 'In stock' item from a real UK dealer....

Chaz.

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There is so many different dies and types of resizing that confuses things.i just stick to fl sizing and bushing fl dies that go with my 7mm  neck turn calbres.i shot prone from 1000yds Sunday using a supershort versapod and my fingers under the butt in timed details and put 15 of my 20 shots inside 1 foot scoring rings inc 9 inside a 6 inch scoring ring so you could say I am happy with my fl sized reloads.

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