Seating in New Brass

[Jaywalker]

A basic question - what's too small to run into a Lee neck sizer?

My collet dies arrived along with my new Lapua brass - 6.5X55. If this were an expander button set, or I werre using once-fired brass, I wouldn't see a problem, but the neck sizer uses a collet/mandrell instead of an expander button. The inside neck diameter is .260 and the bullets are .264. The mandrell doesn't fit easily into the neck.

Is this a case of just force fit it into the neck sizer, or do a full-length size first, or something else I haven't thought of?

Jaywalker

 

[Jaywalker]

Okay, I think I have it figured out. "Neck sizing" is for cases fired in the specific bolt action or single shot rifle. All others should be full length sized. New brass hasn't been fired in my rifle, so it should be full length sized. How's that reasoning? I presume my Lee FL die has an expander button.

Jaywalker

 

[ocabj]

You shouldn't have to resize brand new Lapua brass. I hear about people who resize brand new brass, but most people who use Lapua don't even bother. Just open the box and inspect the brass to see if there are any anomalies, and just load them up. The only thing I do with brand new Lapua is to debur the flashhole. Even though the holes are drilled instead of punched, I still see burrs.

And I've only had one box of Lapua that needed neck sizing. I bought a few 100ct boxes from Midway and one of them had about 25 cases with a dinged neck. If you look down on the brass, the neck doesn't look like a perfect circle, 'O', but instead it looked more like a 'D'. I ended up neck sizing all 100 in that box so it would be consistent.

 

[Jaywalker]

ocabj,

Are you saying that it's okay to seat a .264 bullet in a .260 neck? Or that it's okay to force a too-large collet/mandrell into a too small neck?

Jaywalker

 

[sid k]

The mandrel for the Lee collet die is a little larger than the expander ball on your full length sizer die. Lee says that if you force the bullet into the smaller neck created by the FL die you will have some alignment problems caused by the uneven neckwall thickness on most brass. From my experience he is correct in this, but I felt that the bullet was held too loosely in my 260 for hunting purposes and ordered an undersize mandrel from Lee for about $3. I load three other calibers with the collet die with no trouble.
Sid K

 

[ocabj]

Are you saying that it's okay to seat a .264 bullet in a .260 neck? Or that it's okay to force a too-large collet/mandrell into a too small neck?

I was just saying that you shouldn't worry about resizing the brand new Lapua brass, neck or full length.

As far as the .264 bullet in a .260 neck, that's normal. The neck tension is all that holds the bullet in place.

As far as a too large mandrel question, I have no clue. I'm assuming you bought the Lee deluxe die set? I have a set in .308, I haven't measured my .308 collet die's mandrel before. Have you tried resizing a piece of once fired you have laying around using the collet die to see what the resulting inside diameter is?

 

[Jaywalker]

Sorry, but I'm still missing the point.

These are new brass and, out of the box, they have a .260 inside neck diameter. I understand that a .260 inside diameter would be fine, once the .264 bullet was in it, but do I put a bullet in the neck that's now .260? Or, do I neck size it with a mandrell that also doesn't go in easily? Or, do I FL size it, most likely, since the expander ball might fit better.

Most of my choices seem to lead to buckling the neck, unless I'm missing something.

Jaywalker

 

[only1asterisk]

Go ahead and seat the bullet, you shouldn't crumple the neck. A bullet should never fit into a sized (or ready to load) neck. If this brass were not Lapua you may need to size it before it's first loading, but as ocabj said most people don't bother with lapua or other premium brass unless there is a specific reason.


David

 

[Jaywalker]

Okay, thanks. Chamfer the inside of the neck and Seating Die only.

Jaywalker