Lee Full Length Sizer vs Collet Neck Sizer?

[nipponese]

I just received my Lee Deluxe 308 die set and I'm seeing two sizer dies, the Full Length Sizer and Collet Neck Sizer. Frankly, I don't understand the difference. According to the manual, the Full Length sizer is for brass fired by a different rifle, is that correct?

Anyway, they both have de-cappers, so my question is, am I correct to only use one of these dies and not both?

[bohoki]

if you are using an autoloader use the full length

[gunboat]

General thinking is that a case reused in the same weapon only needs to be neck sized -- after a number of firings the case will require full length sizing.
Semi-autos and often pumps may require full length sizing after each firing.

[gorblimey]

Given the considerable energies involved and the danger to bystanders, OP would be wise to carefully study a proper manual wherein topics such as this are handily addressed. Lyman 49th ed is a good default.

[ejhc11]

Yes - like what others say get a new reloading manual, and this supplemental book is also recommended

http://www.amazon.com/ABCs-Reloading-Definitive-Novice-Expert/dp/0896896099/ref=sr_1_1?s=books&ie=UTF8&qid=1300795684&sr=1-1

If you're shooting a semi-auto .308 you need to use the full length resizer. If you are reloading from brass shot from the same bolt action and going to shot in the same bolt action rifle you can use the collet die which is "neck sizing." Using the collet die will usually put the least strain on brass and prolong its life and a little more accuracy for the bolt action rifle.

[nipponese]

All, thanks for the advice, I'll get these manuals right now.

[wbrosha]

Or for the best of both worlds remove the depriming pin form the collet sizer and run both through the 4 turret system. FL sizer first the collet.

[J-cat]

That won't work as the FL sizer will swage the neck so tight the decapping stem of the Collet die won't fit.

I'd ditch the FL die and get a Redding body die.

[wbrosha]

That won't work as the FL sizer will swage the neck so tight the decapping stem of the Collet die won't fit.

I'd ditch the FL die and get a Redding body die.

That is why I said remove the depriming pin. I have done this with thousands of 308 rounds and it works just fine.

[J-cat]

So how does the collet work then?

[gorblimey]

That won't work as the FL sizer will swage the neck so tight the decapping stem of the Collet die won't fit.

I'd ditch the FL die and get a Redding body die.

The machining of the necker mandrel tip is rather coarse. I find the die feel and function is much improved after polishing the hell out of the mandrel tip, the surfaces involved in squeezing the collet, and the neck area of the collet interior. Once polished, the mandrel tip does a lot better with tight necks.