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Body Die & Collet Die or FL & Collet?

I am just starting to use a Collet die & have some questions. When using a Lee Collet die I assume that I should be using a body die & not a FL die and then the Collet die. Is there any harm in using a FL die & then a collet die?

As far as order I plan on the following:
- decap
- body die to push shoulder back 0.002"
- Collet die

If I use the Willis collet die for the belted magnums where in the reloading process should I use it?
 
Body die will not do what you want to do youll need a FL die to actually resize and push the shoulder back. Get a FL bushing die made for your chamber and itll do everything in one die
I thought that a body die would size everything but the neck (reduce body diameter & push shoulder back) - is that not the case?
 
For my 6.5 CM I have a Lee Collet Neck size die, a Forster Shoulder Bump Die, a Redding Body Die and a Forster Full Length Die.

I checked for bullet Run Out on each type with the 10 loads each. The results were:
Full Sized with Forster Die was the best with .0005" to .0015" with the majority .001" or below.
Body Size with Redding Die and Lee Collet Neck die ran .0005" to .0015" with the majority between .001" and .0015"
Lee Collet and Forster Shoulder Bump was .0015" to .005" majority were .003" and down.
Not a lot of difference with full length and Body size Collet Neck size, but just Neck sizing does leave a bigger variance.
Testing done with RL26 and Nosler 140 CC bullets showed Body Size with Redding Die and Lee Collet Neck die to give the lowest SD, for some reason the Full Length sizing would give a shot with a large ES, checked it 2 days in a row with 48.5 gr and 47.5 gr. with same results.
Your results could be different.
I will continue with testing between Body Neck vs Full Length until I have enough data to make a decision of which method to use.
 
I thought that a body die would size everything but the neck (reduce body diameter & push shoulder back) - is that not the case?
My Redding Body die sizes body only and bumps shoulder back according to which Shell holder I use from the Redding Competition Shell Holder set, it changes by .002" per shell holder so you can get the bump you need. It does not size the necks.
 
Body die will not do what you want to do youll need a FL die to actually resize and push the shoulder back. Get a FL bushing die made for your chamber and itll do everything in one die
And you can control exactly how much the shoulder is set back by using a set of Redding competition shell holders. This let you account for different manufacturers of brass without having to adjust the sizing die.

Consistentancy is the name of the game

David
 
My tests on how straight sized cases are has got the best results with a one-piece full length sizing die whose neck is about .002" smaller than that of a loaded round. That makes the case mouth/throat diameter about .001" or so smaller than bullet diameter. It's called an "interference fit."

No other die keeps the case body, shoulder and neck in perfect alignment while reducing fired case dimensions. Redding and RCBS bushing dies have a small clearance between the bushing and its chamber holding it. That lets the bushing align to the case neck that goes into it. Sized case necks and shoulders are not always perfectly centered on case bodies, but the small spread is not a big issue. Sierra has used Redding FL bushing dies for years reloading cases to test their bullets.

Body only dies do the same thing as full length sizing dies set to squeeze down part of the neck; they push the fired case shoulder forward increasing case headspace that often causes the bolt to bind as it goes into battery. This prevents the bolt head from positioning itself at the same place each time reducing accuracy a little. A thousandth or so case head clearance is ideal, in my opinion.

Redding's Competition Shell Holders have been one of the best things to keep sized case headspace consistent to smallest spread. Whatever that spread is will be transferred to the bullet's jump distance to the rifling lands.

Forster hones their FL dies' necks to customer specs for $12 plus shipping.
 
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I thought that a body die would size everything but the neck (reduce body diameter & push shoulder back) - is that not the case?
You are correct.
- Body die has a sizing chamber to the neck junction.
- F/L die has a sizing chamber to the case end.
- F/L Bushing die has a sizing chamber to the neck junction, and a bushing chamber for the neck portion.
- Neck Die has an alignment chamber to the neck junction, and a sizing chamber for the neck
- Neck Bushing Die has an alignment chamber to the neck junction, and a bushing chamber for the neck portion.
- Seating die has an alignment chamber, and a seating stem
The combination of a Body die + Neck die can accomplish the same thing as F/L dies, in two separate steps. With versatility to control sizing of the entire case body to the neck junction in one step, and then the neck portion in a separate step.
Donovan
 
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Body die will not do what you want to do youll need a FL die to actually resize and push the shoulder back. Get a FL bushing die made for your chamber and itll do everything in one die
Dusty,
With much respect, if you pull the bushing out a FL die what you have left will give the exact same result as using a body die.

Friends and I have done the two step sizing process and for some applications it seems to give slightly better results. One example is when you are working with cases that are not going to get their necks turned.

Some time back a fellow that has a well built .308 was doing some load testing sizing with a good fitting Redding bushing FL die. His necks, had been slightly turned just to clean them up. He was in a mood to experiment, so I suggested that he try using a collet die first and then his FL die with the bushing removed. For whatever reason, his results were slightly improved.

Later, after a layoff, when he started loading and shooting that rifle again, for some reason he went back to the FL busing die, until I reminded him of his previous test, at which point he repeated it, with the same result.

There are a lot of variables that could influence the outcome in a situation such as his, one being whether a powder "likes" a lot of neck tension. In his case he was working with Varget, and that was not a requirement, although he did order and try a couple of smaller mandrels for the collet die. Perhaps if he had been working with a different powder the results would have been different. In any case, I have done the two step process starting back a couple of decades ago for some situations, but certainly not all. The good thing is that if you already have a bushing FL die, it only costs you the price of a collet die to do the experiment, and they are inexpensive.
 
Dusty,
With much respect, if you pull the bushing out a FL die what you have left will give the exact same result as using a body die

Yes sir i was wrong on that. I was already corrected by another friend. Never scared to admit when i am wrong. The ones i have made are like a small base die that hits the shoulder junction too. I copied that off somebody elses dies but evidently it wasnt a redding body die- i dug out an old redding ppc competition set with a body die in it and it does have a neck in it.
 
Is there any harm in using a FL die & then a collet die?

Depending on how much your (non bushing) FL die reduces the neck you may find the mandrel in the LCD will not go in - the o/d of the mandrel may be larger than the i/d of the re-sized neck. Better to take the bushing out of a FL (bushing) die or use a body die then use the LCD.

Also, look at the option of an expander mandrel (such as K&M) to use in conjunction with your FL die.
 
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A couple of things:

Back in the day I experimented with the order of a body die and collet, using a concentricity gauge to choose which to do first. On that day, with that brass, collet first won.

I have also done a similar test comparing using the expander "button" in a one piece FL die in the normal fashion (with lube inside neck) to removing the decapping assembly (including expander ball) sizing the case, and then carefully expanding with an expander die and mandrel. Using the die and mandrel worked better, to a significant degree. Any time that you are expanding with a mandrel you want to use lube in the neck and proceed very carefully being sensitive to the amount of force applied.
 
A couple of things:

Back in the day I experimented with the order of a body die and collet, using a concentricity gauge to choose which to do first. On that day, with that brass, collet first won.

I have also done a similar test comparing using the expander "button" in a one piece FL die in the normal fashion (with lube inside neck) to removing the decapping assembly (including expander ball) sizing the case, and then carefully expanding with an expander die and mandrel. Using the die and mandrel worked better, to a significant degree. Any time that you are expanding with a mandrel you want to use lube in the neck and proceed very carefully being sensitive to the amount of force applied.

I also have done that same test a few times, all with Lapua 6BR and .223 brass. i found no significant difference between Collet die first vs Body Die first. i also have not seen anything on paper that causes me to revisit this. my two cents
 
Body die will not do what you want to do youll need a FL die to actually resize and push the shoulder back. Get a FL bushing die made for your chamber and itll do everything in one die

Aces on that post Dusty Stevens. Got a Forster and had them hone it. Catch flack all the time about not being able to neck size. T.S. Buy a full length sizer as well.
 
Folks, keep in mind that a 'FL bushing die' is not a 'FL die'.
A FL bushing die is normally a body-bushing die.
The function of which can be a separate body die and a separate bushing die.

That said, there are body-bushing dies where the bushing includes shoulder. If this FL sizes necks, then I would never want that.
There is no 'good' in FL sizing of necks.
 

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