Proper neck size for .223 Rem?

[something vague]

I am reloading .223 Remington for my Ruger M77 mark ii. I purchased a Lee Collet neck sizing die and after I went through my first sets of neck sized only rounds I feel as though the neck tension was a bit loose. Seating a bullet in my neck sized cases was much much easier feeling than seating a bullet in a F/L sized case from my RCBS die.

Finshed round with a bullet seated (Sierra 52gr. HPBT) outside neck diameter = .246" consistantly.

F/L sized case without a bullet seated outside neck diameter = .244" consitantly.

Lee Collet neck die without bullet seated outside neck diameter = .245" consitantly.

What is the proper size for outside diameter that I should be looking for before the bullet is seated? Is there enough bullet tension with the measurement I am getting with the Lee Collet die or do I need to sand the Mandrel down? And what are everyone's experience with Lee Collet dies? Do they seem to produce much runout, I don't have the means to measure this?

 

[docsleepy]

OK, I'm sorta a newbie myself but I've reloaded about 200 rounds using the collet die and recently got severeal of my own questions answered:

1) If using a lee press, 25 lbs of force to properly size.
2) be certain that you have the die threaded down until the movable part just touches the ram; then move the ram out of the way and screw the die in 1-1.25 more turns (lee press). Different instructions apply to other presses, mainly to be CERTIAN you don't apply TOO MUCH pressure and ruin the die. It doesn't take that much.
3) do not be afraid to disassemble the die (remember where things went) and observe how it works -- it is pretty simple on the inside.
4) Bullets should be plenty tight enough so you cannot move them at all with finger pulling.
5) be sure that you seat the bullet to proper depth (whatever that is!) to start I used SAAMI specs.

Runout:
You may get less runout if you mark every case with a line, size it with the line one way in the press, the turn the case 180 degrees and size it again. I keep track of that line and put the bullets into the rifle with all the lines the same way.

The runout that I measured (supporting the TIP of the bullet) and measuring runout at the base just infront of the case) was in the range of .002-.004 when seated with a Lee die as well. I switches to a Forster benchrest die and MAYBE cut the runout in half -- but did not eliminate. I was surprised that the reduction from the Lee dies was not more. When seating with the Lee Dies, I use the line again - seat roughly half way, and turn, finish at 180 degrees. I noted no improvement in my 0.5" / 100 yard groups when I switched to the Forster die.

hope that helps
gordon

 

[Doug b]

What does your mandrel measure?

 

[ranger335v]

"Seating a bullet in my neck sized cases was much much easier feeling than seating a bullet in a F/L sized case from my RCBS die."

They are meant to be that way. It helps with loaded round concentricity. Jamming a bullet into a signficantly undersized neck almost guarantees the bullet will tilt as it enters the case.

LOVE what that Lee collet neck sizer does for accuracy!

 

[243winxb]

Here is some reading for you on the Lee http://benchrest.com/forums/showthread.php?t=49899&highlight=%22lee+collet+die%22

 

[something vague]

I have come to the conclusion after some more measurements that I am ending up with .001" of neck tension on my bullets in .223. Is less bullet tension conducive to better accuracy? Or should I aim for a bit more neck tension than .001"? I would hate to sand down the mandrel to find out that my groups open up.

 

[kelbro]

I prefer .002. Try it first at .001 if you like and see how it shoots. Sand it down 'til you get .002 and see how it shoots. You can get a replacement mandrel from Lee for just a couple of bucks.

 

[something vague]

I ordered a replacement mandrel, actually an undersized mandrel by -.001" about a month ago. The day after I ordered it they charged my account including shipping costs. I waited a couple weeks and then called to see if they shipped it. The lady said they haven't shipped it and that they are behind and couldn't tell me when they expected to ship it. It has now been at least another 2 weeks since the call and now I can't get anyone to answer my calls period. Has anyone else around here had to deal with Lee? Anyways, I haven't been able to compare differences in neck tension and how they effect accuaracy. But I was able to get around .0015"-.002" of neck tension be annealling my case necks. They are only twice fired Winchester cases. I will compare accurracy of the annealled cases to the un-annealed cases of the same batch.