Home Forums Hunting & Shooting Ask The Gunwriters Lee Collet Die Issue

Just loaded some rounds. Adjusted the die as recommended. Upon seating the bullets, about 60% of the bullets were tight in the neck, the remaining bullets, while not entirely loose, could be moved sightly with finger pressure. My assumption is that the necks of the brass were not of uniform thickness. Is this a correct hypothesis? Probably would not be an issue if these cartridges were just going to the range, But using them in hunting conditions causes me pause.

Would appreciate the benefit of your experiences, thoughts, and suggestions. (If it matters: 257 Roberts, 100gr Hornady ILs, R-P brass.)

Not a gun writer. I would guess the problem has to do with brass springing. Try annealing your brass or getting an undersized mandrel.

Do a search on here of how to set up these dies by member Mathman
The factory instructions do not work as well
If that doesn’t work take the mandrel out and spin it in a drill and take a bit off the thickness with some 360 grit sand paper, or order an undersized mandrel from Lee

Simple solution... just tighten the die just a hair by turning it say a 1/8 to a 1/4 turn...clock wise...

The die squeezes the neck around a mandrel. The brass thickness shouldn't matter, that would affect your outside neck diameter after sizing, not the inside diameter.
As 375Taylor said above, it sounds like you need to anneal your brass. The loose necks have probably been work hardened and are springing back excessively.
That, or you are not providing uniform pressure on your press stroke.

Seafire’s solution worked for me when I experienced that issue.

Thanks, guys...very helpful feedback!

Is there any concern of pushing the shoulder back and thereby screwing up headspace by screwing the die down lower?

The die doesn't affect headspace, so it won't be an issue.

I have several Lee collet dies that I have had to sand down the mandrel to get better neck tension.

Neil

Sounds like an issue that Lee should address!

They'll sell you a mandrel for a nominal fee. Just need to specify the size you want.

OR you can cut down the one you have.

DF

As mentioned, the brass might not be springing back consistently enough and may need annealed.

Every one of my LCD's with the standard mandrel sized brass with minimal tension. I have learned to order standard and undersize mandrels when I buy a new LCD, and sand the down the mandrel to "fit" different brands/lots of brass.

Put a mic on the mandrel you have now and see what's what.

I find a .002 undersize mandrel is about right. I order from Lee when I order a new collet die automatically now.

Ture. I have three standard size 6mm mandrels, none of them mic the same diameter.

IIRC, the cost of a mandrel is around five bucks, or so. At least that's what I remember from a while back.

DF

How can it be the mandrel when the OP said 60% of the reloads have tight necks/bullets? Technique and brass come to mind here.

Yep, I have found the "springiness" of the brass has much to do with success when using LC dies.

And even though they're more tolerant of uneven neck thickness than expander-ball or bushing dies, uneven necks can still have an effect.

Gentlemen: FWIW: I tried Seafire's advice and that seemed to do the trick.Still puzzled as to why some rounds were initially OK, and others needed an additional squeeze. Must be the "springiness" phenomenon.

Thanks again for all the assistance. That's why I hang around here!.

The simplest solution is always the best solution!

Casey,

Though I prefer simplicity, I also like "Ocham's razor" (the law of parsimony, the problem-solving principle that "entities should not be multiplied without necessity"--or more simply, the simplest explanation is usually the right one. Please note "usually"!

I am curious how many times your brass has been reloaded. Brass doesn't quite age (harden) at exactly the same rate. If it is the same lot of brass, with the same number of loads fired, tightening the die won't always work. It might be worsen if it is a mixed lot with different numbers of firings.

With collet dies and same lots of brass, you can set your die and not need to adjust it. If there are more than three loads on that brass, annealing is the way to go

Good question, Steve. Brass all came from the same bag. This was either the second or third loading. All but 8 firings were 46gr of IMR4350. (Tried 45, 46, and 47 gr with the new brass. Not surprisingly the rifle preferred the 46 gr load) So I would think that the brass has not been over stressed.


Oh, FWIW, the rifle is a M70 XTR FWT.

2nd or 3rd; that is the question. Maybe 4th?

Keep all your brass separate. I anneal after the 3rd firing. It is a simple approach that requires no extra work. It also makes trimming easier by grouping brass.

The issue outlined in this thread, where variable neck tension results from collet-neck-sizing using a die setup that previously produced consistent neck tension, is how I determine when it is time to anneal a batch of brass.

See if you can find Mathman's Lee Collet die instructions. Print it out and put it in your reloading folder. Beats the heck out of Lee instruction.

Seafire is giving you similar info.

DF

Most of my Lee neck sizing dies do fine. Especially if you squeeze, then rotate case 90 deg or so, and give it another squeeze. They have to be adjusted tight like Seafire said also. I have an ‘06 LC that required the drill and emery cloth routine.

Or you can blow the aluminum cap out the top of the die with a compound press.

Don’t ask how I know.

My learning curve damage was covered by Lee CS.

DF

You adjusted the die down too far into the press.

I guess you found out it's best to thread the die in, raise a case into the die and resize. Then try hand seating a bullet into the case mouth. If it slides in, tighten the collet die down 1/8 of a turn, repeating until the case mouth is small enough.

When the die came out, myself and others emailed Lee about that. All we heard were crickets.

Yeah, I got it figured out eventually.

I didn't have Mathman's instructions, was just man handling it. It's amazing what a big compound press can do with some muscle power.

DF

All you have to do is raise up the brass and turn the die in little by little, checking with a bullet as you go. You can use calipers to set the die to a repeatable diameter, or replace the lee lock ring with a Hornady ring.

Most reloaders do not realize that there is a bit of leeway You can tighten up the neck diameter according to how much, or how little, you screw the die in. It only takes seconds to set up. Many people who pop the aluminum tops off believe that dies must be used under a lot of force. Not so. Many years ago, I posted something to the effect that you only need to use one finger to push down on the handle for most reloading operations.. Naturally, some people objected.

I wrote Lee a letter when the collet dies first came out, and laid out a short instruction set, but I never heard from them. Maybe 6 mo to a year later I sent them an email. They thanked me for my input. Nothing changed, of course.

I like Lee, but they could do a better job with instructions.

They need to contact Mathman, work out a deal to use his well written collet neck sizer instructions.

Their version leaves a lot to be desired.

DF

What I do, works fine.

Sadly, they had the improved write up mailed and emailed to them from multiple sources. Mathman was late to the party. Lee has not changed the write up.

It's their business and their decision.

May be hard to admit you need help...

But, if you do, why not suck up your pride and take the offered help.

I still like them and their stuff.

DF

I like Lee as well. Most of their stuff is good. The collet die is one of those well designed items.

As I recall, they were the first out of the gate with the universal decapper, and still offer the cheapest one. I also like their crimp dies and case expander die. Their priming tools have suffered, but after a bad start, they improved their latest bench mounted primer. Because of the foul up with the first version, I ended up using a Lee Ram Prime more - a single feed priming tool for most single stage presses. It is an excellent value and is simple to use. For $16, it was a bargain.

I have never been a fan of their seaters, but like everyone else, we have our preferences in equipment, rifles, trucks, etc. Variety is the spice of life!

I think their seaters can be hit and miss, I like Forster or Hornady seaters, sometimes pick up one if the Lee seater produces too much run out. And, that seems to depend somewhat on the round.

The highest and best use of their FL sizer may be a body die, after grinding out the neck with a Dremel. Cheaper than a Redding body die and works pretty well..

I like to get the Deluxe Lee die set with both collet neck sizer and FL sizer.

DF

Same here, except that I rotate the brass 1/3rd and then 2/3rds for two extra squeezes. Does the trick for me....