Solve My Problem, Win a Prize!

[Matthew T.]

Or at least my undying gratitude.

I tried to seat some bullets for my .243 using my new Lee FL resizing set last night. Here's what happened.

The bullets seated hard and copper was shaved off the bases.

The cases had been FL resized with the shellholder bottoming out on the die.

The case mouths had been chamfered/deburred.

The seat/crimp die was backed far enough out not to touch the case. It provided no crimp.

The case mouth diameter of the resized cases is .238.

The expander at its widest point is .242.

The expander is going all the way in since I've used the die to decap cases.

I called Lee this a.m. They said

The only thing that would cause copper shaving is not chamfering and/or too much crimp.

.238 case mouth diameter is too small. Tech said that would correspond with a .240 bullet diameter (don't know if that exists, except maybe as a wildcat).

Also said the cases shouldn't have that much spring back unless they are nickel. They aren't. They're brass.

Lee is stumped, I'm stumped, and I think I've stumped the Yahoo handloading forum. (I really don't want to use a .30 caliber spitzer to open up the neck of my brass.)

Ideas?

[Mal H]

Are the cases new or used? If used, approx. how many times have they been fired?

The case necks may have become hardened and might need to be annealed or better yet thrown away. Annealing can be done at home, but controlling the temperature during the process is tricky.

What brand are the cases? What bullets are you using? (mfg., diam., style)

[Matthew T.]

The cases are once-fired Remington and Winchester and brand-new Winchesters. New and once-fired cases have the same problem.

[Jbar4Ranch]

1) Try a different brand of cases with your Lee dies.
a) Problem solved
b) Problem not solved, goto 2)

2) Try a different set of dies or expander plug with your current brand of cases.
a) Problem solved
b) Problem not solved, goto 3)

3)

(edit) I see you already tried #1 while I was posting.

[918v]

Welcome to the wonderful world of tight tolerances!

1. Every make of brass uses a different blend of alloy. Some are softer than others. For example, R-P is dead-soft at the neck while Win is rock hard. Seating bullets in these two cases is a completely different experience.

2. I only work with brass that is easy to work with. If you have a chance, try R-P brass.

3. Brass springs back. Some spring back more than others. Hadr brass springs back more than soft brass. Running a .242" expander will not yield a .002" difference in diameter. Due to springback, the difference may be .0025" or .003". I work with a difference of .0005". This allows easy seating and my bullets are not deformed during seating.

4. You should get a K&M expand iron ($15). It measures .2432" and will solve your problem. www.kinneman.com

[Mal H]

Hmm ... I'm stumped along with you and Lee at this point.

As an experiment, see if you can rig up your press so that only the expander ball enters and exits the neck of a previously resized case (i.e., don't resize the case at the same time as expanding the neck). Then remeasure the case mouth.

An additional experiment - remove the expander ball stem, resize a case and measure the mouth. This is to see what the sizing die is doing to the neck.

[LHB1]

Sounds to me like your Lee FL sizing die is out of spec and is excessively reducing the case neck diameter. See if Lee will replace it with another sizing die or buy an RCBS, Hornady, Redding sizing die.

Good shooting and be safe.
LB

[SpentCartridge]

if the cases are soft (fairly new), or have been annealed (a relatively easy process -place brass standing up in a metal container full of water up to bottom of sholder, heat with propane torch until dull red, individually knock them into pan to cool) or you can use a .257 expanding ball, possibly polishing down to .246 or .248.

[caz223]

Yeah, check your sizing die.
Take it apart and clean it.

[Matthew T.]

I took the advice of LHB1 (among others) and am sending the set back to Midway. I just purchased an RCBS standard FL die set from my local store. Tonight, we will see if my problems continue.

[Rico567]

This is a really hard case (so to speak...) to understand. As I understand all the rifle size dies I have ever used, when a rifle case is sized, the die forces the case neck down to a diameter below minimum. As the case is withdrawn from the the die, the expander ball expands the case neck to ensure that the neck ID (inside diameter) is going to be compatible with the bullet, i.e., that the neck ID will be a few thousandths smaller than the nominal bullet diameter, so that the bullet will be a "spring fit" in the neck.

Relevant facts stated in the original post:

The case mouth diameter of the resized cases is .238.

The expander at its widest point is .242.

If the expander was expanding the case necks to or near the diameter given, seating should be no problem. As I must assume that the expander ball is being drawn through the case neck (or the case couldn't be withdrawn from the die....), the inescapable conclusion is that too much springback is occurring in the case necks. Since this is occurring with different makes of brass, with different numbers of firings, this is indeed a puzzling situation. The previously advanced theory of hardened case necks would be my assessment, but with the variety of cases that have been tested, that just shouldn't be happening.....

I suggest:

1) If you have access to another set of .243 dies, try a batch with them.

2) Be sure the inside of the case necks have some lube when sizing them.

3) I'm uncomfortable suggesting this, but as it is not mentioned in the original post, have you checked the bullet diameter? Sounds like it's barely possible that somebody packed .257 bullets in the .243 box....that'd be about right for some heavy shaving.

[Matthew T.]

Rico567,

1. Will do.
2. I'll try it.
3. I measured the base of a Nosler Partition at exactly .243.

Thank you for the suggestions.

[LHB1]

Matthew,
To further clarify source of problem you can buy one box of new brass and try the new dies with both previous brass and new brass. This should point out where the problem was occurring.

Good shooting and be safe.
LB