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308 dies neck size only


Richiew

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Hi all 

happy will the dies at present ie redding and Forster ,neck size and decap with internal neck sizer .question is would I get more coeccentric ness if using neck die type which doesn’t have an expander ball and just has bushes to set neck tension . If decap pin/expander ball is only a bit not central then it’s going to pull the case neck a bit skew on the way out . Also has anyone tried the 21st century contricity  gauge , thanks in advance 

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Expander ball type dies can feel and maybe harsh on unlubed brass? I personally don,t like them.This is what I would do and go some way to doing all that is necessary in one movement. Purchase a Redding Bushing style FLS die and a set of comp shell holders.This die and selecting the correct neck size bushing together with the correct shell holder to set minimum headspace will probably make the best custom fit case for your rifle.Any remaining concentricity problem will be with the case neck when formed at its making and only neck turning will reduce this. This is by no way the only way forward,,,others may give some more suggestions.Do you actually have a runout problem to begin with and have measured it?,,,,,O

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Personally I wouldn't bother with the neck sizing only route as sooner or later you are going to need to bump the shoulder back any way.

From personal experience Forster FL dies are excellent. I use them in 4 different calibres and when set correctly they produce cases with minimal run out on the neck - typical 0.001 or less. I use Forster micrometer competition seater dies and they produce loaded rounds to the same run out. Yes the brass is worked more in the neck area but I anneal anyway so its a moot point.

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If you use a neck-only die, you also need to use a body die alongside on most cartridges, unless running with very low loads / pressures. Cartridges in the 308 Win 'family' (308, 7mm-08, 260, 243) for instance will see the shoulder move forward enough on a single full-pressure firing to give tight chambering for maybe half the cases on the next loading, and the need to force the bolt-handle down on some cases in a third go. (This also shows up as witness marks on the shoulder and circular marks on the case-head as the bolt is turned against it on opening whilst under considerable pressure.) A longitudinally tight ('negative headspace') case to chamber fit of varying degrees does nothing much for consistency and precision and I have read that it also causes chamber pressures variations, although I can't see a mechanism for those to be produced.

In times past I ran cartridges like the 308 Win sizing them with a Lee Collet die only quite happily, but with what I'd now regard as very modest loads and pressures. Returning to this particular tool on a 260 a couple of years back, I was taken aback as to how rapidly shoulders move with the pressure levels I run at these these days.

The obvious alternative is a FL die, but standard models are brutal on the case as they over-size necks down considerably and then expand them heavily. A much better alternative is a bushing-style FL design or a Lee Collet + body die. I'd give three options, although there are likely more:

1) Forster Bushing-Bump sizer. This is a bushing neck-sizer, but whose die body also moves the case shoulder (ie 'bumps' it), the latter function set as per a normal FL die according to how much the die is screwed down in the press in relation to the shellholder. I use this type in both 223 and 308 FTR rifles with minimum SAAMI chambers. Despite running at some hefty pressures, I've never seen the need to FL size the case and after multiple firings Lapua Palma cases still chamber and extract very easily and with occasional annealing brass life is very great indeed in the 308 with its strong case-head. (223 brass goes in the bin after a few firings for expanded primer pockets.) However .... the Bushing-Bump die doesn't incorporate an expander ball, so unless neck-turned brass is being used, either one should be fitted or a separate expansion operation using a mandrel type die / expander employed for best results.

2) Redding Type S full-length bushing sizer. It works as per a normal FL die, but the degree of neck working is controlled by selecting a bushing size to match the brass in use and to size necks down only just enough so that every case is felt to go over the expander button, ideally slip over with so little resistance that you only just feel expansion taking place on the press handle. Redding also offers aftermarket carbide expander buttons which reduce brass working further.

3) An alternative either little known here, or if mentioned, scoffed at - Lee Collet NS die plus Redding (or other) body die in combination. This has become increasingly popular in Canada and the USA among FTR shooters, especially those using 223 for mid-range competition where the little cartridge is now regarded as the equal of 308, if not its superior. The body die gets the shoulder sorted and the Collet does the neck giving excellent consistency and concentric results with minimal brass working and no extra expense in bushings. It doesn't need the inside of the case-neck lubed which is in itself a big plus for many. IMO, this is an excellent method which I'll sometimes use myself, but the Collet's biggest downside these days is Lee's production quality - early examples many years ago were a joy to use while today's seem rough and often an over-tight internal parts fit, so people end up polishing the collet tines whose sharp edges to smooth up die operation and also to stop over-sharp internal edges chewing the neck surface up. 

 

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They should have. The expander button can be dispensed with if required and the die will still decap cases as there is a decapping pin retaining collar separate from the expander button.

http://www.redding-reloading.com/online-catalog/118-type-s-bushing-dies

The carbide expander upgrade involves a new stem and converts the button to floating operation. The Type 'S' FL die in this form is an excellent piece of kit - expensive though!  

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2 hours ago, Laurie said:

They should have. The expander button can be dispensed with if required and the die will still decap cases as there is a decapping pin retaining collar separate from the expander button.

http://www.redding-reloading.com/online-catalog/118-type-s-bushing-dies

The carbide expander upgrade involves a new stem and converts the button to floating operation. The Type 'S' FL die in this form is an excellent piece of kit - expensive though! 

Your correct,,,,,they are supplied as you say with the expander button,,,,do you know I have never used these dies in this way! sorry to confuse the issue for the OP,,,,,,,,,O

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thanks for the relies , lots to try out and think about , was looking at getting just a universal decapper then forster dies with bushing only . think they come in 308 with bushes for 6. 4 and 2thou  neck sizing for tightness on the bullet -hope this makes sense .

cheers rich 

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My routine for all my full bore calibers. I use redding body dies with competition shell holders to set the shoulder back.

I then use a L.E.Wilson neck sizer bushing die.

I record everything on a spreadsheet so I have a record of the cases life.

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Hi one hole 

just being reading the posts again and picked up on your comment re runout , not had the made up bullets measured as yet but they do sometimes look as though the neck is off centre after the case has been sized .started off with redding dies and found the return stroke to be very stiff as it expands the neck ( using the graphite media ) changed to forster dies with a ball type expander rather than the barrel redding type and the effort of expanding has dramatically reduced . Also the forster dies seem to be less fussy to get the decap pin to be central when looking down at the open end of the die . next step might be to check runout before going too far into the bushing etc route .What do most people do to check runout ?????

cheers  

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13 hours ago, Richiew said:

Hi one hole

just being reading the posts again and picked up on your comment re runout , not had the made up bullets measured as yet but they do sometimes look as though the neck is off centre after the case has been sized .started off with redding dies and found the return stroke to be very stiff as it expands the neck ( using the graphite media ) changed to forster dies with a ball type expander rather than the barrel redding type and the effort of expanding has dramatically reduced . Also the forster dies seem to be less fussy to get the decap pin to be central when looking down at the open end of the die . next step might be to check runout before going too far into the bushing etc route .What do most people do to check runout ?????

cheers

Quite a few concentricity gauges available out there and highly recommended for the serious reloader. I made my own checker utilising a V block and guage set up and securely mounted on a solid platform,,,works pretty good and tells me what I need to know. A quick and easy method is to place a piece of white A4 paper or card on a flat surface with a light source above,,,roll an assembled round on the card to see any bullet wobble,,,,its very surprising what the human eye can detect,,,you will see a couple of thou wobble quite easily...

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  • 2 months later...

Curiosity got the better of me  so ordered the hornady coentricity gauge . lovely bit of kit ! .tested my loads today and the last batches made using the forster dies in 308 with 155 tmks ,155 amax ,155 lapua L and normal scenars also berger 175s and 185s  ALL were less than 3 thou run out most 1 thou , so very happy with my home loads .

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