Home Forums Reloading Big Game Rifles Lee neck sizer die broke

I had a lee neck sizer die break it stripped the treads at the top of the die it was weird I had gone though almost 20 cases and heard a pop it had never crushed a neck or any thing I will be calling Lee on Monday. I think the threads were crossed threaded has any one else had that happen?

How hard were you leaning on it? How would it crush a neck? miles

The caps are made out of aluminum as a safety feature, to keep from breaking other things like your press.

This is the primary reason Lee says in their instructions to only put 25# of downward pressure on the press lever and not to set the press to cam over

I popped one on a 22-250 die. IMO the Lee Collets for the smaller calibers have less threads and will take less pressure before popping

Let us know what Lee says

Yup, and if you were camming over the press, you are sure to blow the top off sooner or later.

Not if you set it up correctly.

John

I have three other calibers using the collect dies. In the past if the die was not set correctly I would smash the shoulder. I will talk to Lee.

Not really, setting up the Collet die correctly is to follow Lees instructions. If you wish to set your up differently(incorrectly) that's up to you.

Here is how it is done Correctly.

ADJUSTMENT FOR LEE PRESSES
Screw the sizing die in until it contacts the shell holder,
plus one turn more. Run a case into the die. You will feel
the primer being extracted, then the lever will come to
an abrupt stop. At this point, the lever must be pushed
firmly (min. 25 lbs.) to close the collet and size the neck.
Extra bullet grip can be obtained by screwing the die in an
additional quarter-turn.
Other brands of presses that toggle or snap over
center at the end of the stroke provide no feel and can
damage the collet neck sizing die if adjusted as above. We
suggest the die be screwed in until the die contacts the
shell holder, plus 2 FULL TURNS This will prevent
the press from toggling over

If you are smashing the shoulder, take the die apart, do a little polishing and lube the mating surfaces. Something is hanging up inside.

To OP thinking you had it set to "cam over" that is when you lower the press down fully and go down slightly more and feel that extra pop, that is camming. The pressure pushes the rod up against the cap and it pops off the top of the die like you experienced. I would recommend a different die if you want to "cam over"?

I use a lot of collet dies and when I first was starting I stripped one. My fault I was really leaning on it, trying to get good neck tension.

My solution was two fold,

First the key to good neck tension is the proper size mandrel and not working with over worked brass. These days I just order .001 or .002 under size mandrels, but you can "turn" them down with some emery cloth and a drill. Its a shame that lee doesn't just ship the .001 undersize with the collet die, but work with what we must.

If you using the proper size mandrel it only takes a few ft/lbs of force to size necks so its unlikely that you will ever op one of the tops again

Second I bought two of the aluminum caps, one to replace the one I stripped and the other to sit in readyness for the next time I screw up. (for me the cost is not that important its the down time that I hate.) so I have a supply of spares for things that I might break.

That version of "correctly" is for non cam over presses. John and I have taken the time to set up the dies correctly for our presses.

I'm using an old RCBS Rock Chucker with the collet dies set to properly size the necks with a full press stroke. I'm near the ten thousand round mark on my 308 die alone, and I haven't popped a die cap yet.

Part one yes, not part two.

Part two:
Other brands of presses that toggle or snap over
center at the end of the stroke provide no feel and can
damage the collet neck sizing die if adjusted as above.[/b] We
suggest the die be screwed in [b]until the die contacts the
shell holder, plus 2 FULL TURNS This will prevent
the press from toggling over

The mistake is thinking toggling over must take a lot of force. When nothing is in the press, it toggles over with zero force. So clearly there's a middle ground. Just screw the die into the press so the neck is sized correctly when the press makes a full stroke, but screw the die in no farther. It's really easy.

You can set your press to toggle over but run greater damage of damaging the bottom of the die.

If you totally understand the function of the die then you realize that once you have compressed the collets onto the neck brass and thus the neck brass onto the mandrel, it will not matter how much more pressure you put on it, no more sizing will occur. You can not put enough pressure to thin the neck brass or compress the steel mandrel. This takes about 25# or so

For me I just run the lock nut up to the top of the threads



This will put the lever at the most horizontal position



If you want more neck tension then order smaller mandrels from Lee

I do totally understand how the die works, and that's why I know how to set it up with a full ram stroke without springing anything.

I set mine up to cam over also. Properly done it runs no danger of stripping the aluminum cap and I feel it gives more consistent results than trying to put 25# of force on the arm by feel. If you don't set it up right then you can certainly put too much force on it with a rockchucker. Lee's instructions are an attempt to make it idiot proof, but setting them up that way sacrifices consistency that can be had by using the cam over feature. If it's done correctly then ignoring lees instructions and setting it up to cam over is certainly the better method.

Same wavelength here.

Been using all of mine for about 10 years set up this way.

I like mine with the handle near straight out when applying pressure to the die. miles

No, that is how to do it in accordance with Lee's instructions. It is certainly not the only correct method. I fail to see how another method that works well and takes the guess work out of how much pressure to put on the handle each time you size a case is "incorrect." I set all my collet dies up with a very slight cam over and have yet to blow a cap off. I do not have to guess if I am putting 25 pounds of pressure on the handle because if it is camming over, it takes the same amount of pressure every time. If your mandrel is too large, and they often are, no method will work well including Lee's instructions. I suspect that Lee chose the method they put in the instructions as a safeguard against customers blowing a cap off, but that does not mean that you cannot obtain even more satisfactory results with a correctly sized mandrel and very slight cam over.

John