Lee Collet Neck Die...something isn't right!

[Ingwe]

I am hoping that you fellas can advise me on what I am doing wrong. I am using a Lee Neck Sizing Die in my Redding Big Boss Press and trying to neck size for my 7mm Remington Mag. I am also using a Torque Wrench, all according to instructions.

Here's what is going on:

I have the torque wrench/handle in the 2:00 position set to 25lbs, with the die touching the shell holder plus one turn more. When I run a case up and the wrench clicks, I check it with a bullet, but it does absolutely nothing to create neck tension.
I increased the torque in steps and only began to get a bit of tension when I reached 55lbs so something is definitely wrong.

Just a thought.....Since the shell holder does contact the ram, it doesn't seem like the ram is able to push the casing into the die very far. Does this sound right??

I am hoping to get some advice here since this is driving me nuts!

Thanks!!gun)

 

[g0rd0]

I use the collet dies for my 7rm and 3030 pistol. This is what I do first take the die apart and clean it with diesel fuel, dry well then put 1 drop of fine sewing machine oil on the upper part of the collet that contacts the inside of the die not where it contacts the brass. Put the die together and mount it on your press with the ram and shell holder all the way up screw the die down to touch the holder, lower the holder and then screw down the die 1 full turn.
I donot use my torque wrench, what I do is feed the brass into the die and watch the shell holder push up on the collet release preasure spin the brass and repeat. You can feel the collet and the torque wrench is not needed, but, the spin of the brass is needed.
After every 100 rnds I take apart the dies, clean and reasemble

 

[flashhole]

Your die is not screwed down far enough. Experiment with a case by screwing the die down further and further until you get the neck tension you want. You can measure both inside and outside neck diameter with a pair of calipers. The instructions are a good guide for starting but you just need to adjust it down until you get the tension you want.

You might also measure the diameter of the mandrel in your die. The brass cannot be squeezed down any smaller than the diameter of the mandrel. If the mandrel is too big you can take it down a bit with fine emery paper spinning it in a drill or tell Lee and they will get you a replacement.

The tell-tale sign you are putting too much pressure on the brass is the slots between the flutes on the collet show up on the brass neck as fine vertical lines. Spin polish one in a drill and examine it with a magnifier each time you size it.

The last thing I can suggest is to anneal your brass. It may be too work hardened to neck size and you are getting excessive spring back.

The dies work great when they are adjusted properly. I have several. I had one for my 25-06 that was out of round, sent it back to Lee and they sent me a new one. I chased my tail in circles for a while before I figured out what the problem was.

 

[Ingwe]

Thanks so much fellas!

What should my mandrel measure.....maybe it's that

 

[flashhole]

Mine measures .2815. Bullet diameter is .284 so the difference is the amount the inside of the neck is reduced in size to put tension on the bullet. In my case I get .0025 neck reduction.

 

[Kennibear]

FYI
Lee sells undersize mandrels for a nominal cost. As I recall the shipping cost the most.

 

[jsthntn247]

First make sure you are setting the die up right. Keep screwing the die down further and measuring the neck with a micrometer until you see the neck getting smaller. Once you do, screw the die in very slightly and take a bullet and try to seat it by hand, if you can, screw the die in further until you can't seat it by hand and that is where you want to lock it down. Once it's locked down and you load bullets and seat them, measure the outside of the case necks before and after seating a bullet and that will tell you how much neck tension you are getting. If you want more, you can take the mandrel out of the die, chuck it in a drill and file it down with emory paper. Measure the mandrel before you start taking material off and only take off .001 at a time and neck size a piece of brass and measure it each until you get your desired neck tension. My I just did this the other day for my .243, I was getting less than .001 neck tension with the madrel from the factory, so I turned .002 off of it with a drill and emory cloth and now get .0025 tension.