Tip for those using Lee Collet dies

[Kenny474]

I have found that consistent pressure on the press handle is necessary to produce consistent neck tension when using Lee Collet dies simply because of their design. Too little pressure, and neck tension is light. Too much, and you deform the neck a bit. I understand that neck tension is basically regulated by the mandrel's diameter, but uneven pressure will still give variance, and we all strive for perfection. Well, as close as we can get anyway.

What I have done to try to be more consistent when using the Lee Collet die, is make an adapter for my Lee Challenger press so I can replace the handle with a torque wrench. It still operates much the same, but I can set the torque wrench so that I apply the same pressure to every case, improving consistency dramatically over trying to do it by feel.

Basically, when the wrench clicks, you stop applying pressure. Simple and effective.

I plan to take some pictures soon, so that any who want can copy it.

 

[bozo699]

Kenny,
I think this is a novel idea but I am not sure if a torque wrench will click consistantly @ the same pressure. What I am trying to say is a torque wrench is calibrated to be close as in foot or inch lbs for automotive work, where in bullet tension you are talking in the .ooo of inch lbs you need to be the same every time. I guess it would be worth a try though. I wonder if you could hook up a digital scale to the press?
Wayne.

 

[Kenny474]

Wayne, while your "average" torque wrench probably wont be super accurate, it's still a heck of a lot closer than you will get by feel. But I have a real nice in/lb torque wrench, consistent + or - .5in/lb, which when you consider what you are actually doing with it, is extremely accurate.

Anyway, even a normal torque wrench accurate to within 1 or 2 ft/lbs is still plenty close, and a lot better than going by feel alone. I doubt most can feel 2 ft/lbs difference in handle pressure, as you would be amazed how little the feel changes when adjusting the torque wrench in even 5ft/lb increments.

Measuring the necks ID with a micrometer, it seems to work very well. Far better than feel alone, as I have less than half the variance as I did previously.

 

[bozo699]

Kenny,
Thats awesome I wouldn't have thought it to be accurate enough. Keep us posted.
I use a redding t-7 press now but maybe I could adapt?
Wayne.

 

[bigedp51]

Below is a very good article from Benchrest Central on how to adjust your Lee collet die on a RCBS RockChucker type press that goes over center at the end of the ram stroke. The basic problem is "some" of us apply "too" much pressure on the collet die and run into problems. What is important here is uniformity and adjusting the collet die as per below you are using the "mechanical stop" of the press to achieve crimping uniformity on each neck sized case in your Lee Collet Die.

NOTE: If you are leaving compression marks on your case necks you are using too much force.


Using The Lee Collet Die.
By John Valentine.
Benchrest Central

I started using Lee collet dies when they first came on the market and have found that they are very good for the purposes for which they were designed. I have found that there is a lack of understanding of how to use the die properly and as a result people fail to see the advantages that the die can deliver over standard neck sizing dies. This is not the fault of the product , it is just a lack of understanding of how the die works and what it will feel like when you operate the press correctly.

Standard dies use a neck expanding ball on the decapping rod and size by extruding the neck through a hole and then drag the expander ball back through the inside neck. The collet die achieves neck sizing by using a split collet to squeeze the outside of the case neck onto a central mandrel which has the decapping pin in it’s base. One advantage is that there is no stretching or drawing action on the brass. The inside neck diameter is controlled by the diameter of the mandrel and to some extent by the amount of adjustment of the die and the pressure applied to the press.

This results in less misalignment than can occur in standard dies because of any uneven neck wall thickness in the cases.Cases will last longer in the neck area and require less trimming. If cases have very uneven neck wall thickness then this can cause problems for the collet die they definitely work smoother and more accurately with neck turned cases but it is not essential.

When you first receive the die unscrew the top cap and pull it apart check that everything is there also that the splits in the collet have nothing stuck in them then inspect the tapered surface on the top end of the collet and the internal taper of the insert to make sure there are no metal burs that might cause it to jamb. Next get some good quality high pressure grease and put a smear onto the tapered surface of the collet. Put it back together and screw it into the press just a few threads for now. The best type of press for this die is a press of moderate compound leverage that travels over centre.

Over centre means that when the ram reaches its full travel up it will stop and come back down a tiny amount even though the movement on the handle is continued through to the stop. eg. is an RCBS Rockchucker. This arrangement gives the best feel for a collet die sizing operation. Place the shell holder in the ram and bring the ram up to full height then screw the die down until the collet skirt just touches on the shell holder, then lower the ram. Take a case to be sized that has a clean neck inside and out and the mouth chamfered and place it in the shell holder. Raise the ram gently feeling for resistance if none, lower the ram. Screw the die down a bit at a time. If you get lock up (ram stops before going over centre) before the correct position is found then back it off and make sure the collet is loose and not jammed up in the die before continuing then raise the ram feeling for any resistance, keep repeating this until you feel the press handle resist against the case neck just at the top of the stroke as the press goes over centre and the handle kinder locks in place.

This takes much less force than a standard die and most people don’t believe any sizing has taken place. Take the case out and try a projectile of the correct caliber to see how much sizing has taken place.
If it’s still too loose adjust the die down one eighth of a turn lock it finger tight only and try again .
Once the die is near the correct sizing position it takes very little movement of the die to achieve changes in neck seating tension. This is where most people come undone , they move the die up and down too much and it either locks up or doesn’t size at all.

It will still size a case locking it up but you have no control over how much pressure is applied and some people lean on the press handle to the point of damaging the die. A press like the RCBS Rockchucker, that goes over centre each time gives you a definite stopping point for the ram and the pressure that you apply.

There is a small sweet spot for correct collet die adjustment and you must find it , once found , how sweet it is ! Advantages : With a press that travels over centre it is possible to adjust the neck seating tension within a very limited zone. No lubricant is normally required on the case necks during sizing.

If you still cant get enough neck tension to hold the bullet properly for a particular purpose then you will have to polish down the mandrel. Be careful polishing the mandrel down and only do it a bit at a time as a few thou can be removed pretty quickly if you overdo it.

You can't get extra neck tension by just applying more force. The amount of adjustment around the sweet spot is very limited and almost not noticeable without carrying out tests. For example, to go from a .001 neck tension to a .002 or .003 neck tension you would be talking about polishing down the mandrel.

There are some other advantages but I will leave you the pleasure of discovering them. One disadvantage that I have found with the collet die is that it needs good vertical alignment of the case as it enters the die or case damage may result so go slowly.

Also some cases with a very thick internal base can cause problems with the mandrel coming in contact with the internal base before the sizing stroke is finished. If pressure is continued the mandrel can push up against the top cap and cause damage . If you are getting lock up and cant get the right sizing sweet spot, then check that the mandrel is not too long for the case you can place a washer over the case and onto the shell holder and size down on that. It will reduce the length of neck sized and give the mandrel more clearance. If it sizes Ok after adding the washer then the mandrel could be hitting the base. This is not a usually problem once you learn how to use them.

The harder the brass is the more spring back it will have so very hard brass will exhibit less sizing than soft brass because it will spring away from the mandrel more. If this is happening to excess then use new cases or anneal the necks. Freshly annealed brass can drag on the mandrel a bit in certain cases because it will spring back less and result in a tighter size diameter. I have experienced it. I always use some dry lube on the inside and outside if I get any dragging effect. Normally you don't need lube.

I make up a special batch 1/3 Fine Moly powder. 1/3 Pure graphite. 1/3 Aluminiumised lock graphite. Rub your fingers around the neck and It sticks very well to the necks by just dipping it in and out and tapping it to clear the inside neck. After a few cases it coats up the mandrel. Other dry lubricants would work also. Use the same process for normal neck sizing also.

I noticed a definite improvement in the accuracy of my 22-250Rem. as soon as I started using a Lee collet die instead of my original standard neck die.

Readers are encouraged to utilise the benefits of responsible reloading at all times. Although the author has taken care in the writing of these articles no responsibility can be taken by the author or publisher as a result of the use of this information.
John Valentine. © 21/01/2002.
*****

Last edited by J. Valentine; 03-14-2008 at 01:10 AM.

http://benchrest.com/showthread.php?49899-Lee-Collet-Die-Adjustment

 

[Kenny474]

Bigedp51, I set my press up in much the same manner. But as it's not a rockchucker, and the stop isn't as firm as I would like, this tends to help me get the best sizing possible on this specific press as it doesn't cam over or have a definite firm stop.

If you watch Lee's instructional video, they also suggest an amount of pressure to use on the down-stroke of the press. I have simply come up with a way to measure and accurately repeat the pressure needed to accurately size a case.

I do understand the article you posted, and appreciate you doing so. But there is little there I do not know, and most I already use in practice myself. And even with proper die adjustment, I still could not get results as accurate as I would like on this press. And since I use it quite often at the range when using collet dies, I felt that an improvement was necessary.

I have better results on my Lee Classic Cast press, as the stop is much firmer. But, it's bolted to my bench in my basement and I wish to leave it there.

Thanks for the article, I do appreciate it.

 

[bigedp51]

Kenny474

I understand and didn't mean to hijack your posting, the majority of us don't have a torque adjustment knob on our elbow and tend to apply too much force using the Lee Collet die.

I had two problems with my Lee Collet die:

1. Chronological gifted eyesight.
2. And a defective collet that left marks on the necks.

The collet below had the same rough edges on the inside crimping area of the collet. I couldn't see the problem and chocked it up to cheaply made dies and let the dies gather dust.

After again reading glowing praise online for the collet die I broke out my visor magnifiers, said a few colorful words and ordered a new replacement collet.

Now the case necks no longer have Pit Bull bite marks on them and I couldn't be happier with the runout results.

The type press being used and die setup can vary a great deal, below a YouTube video of a Forster Co-Ax press going over center with the Lee Collet die.

http://www.youtube.com/watch?v=RZEas38vkKg

 

[BoydAllen]

Nice pictures.
On the last one, the usual setup for measuring case straightness is to put the support on the case body just where it meets the shoulder and to cantilever the shoulder and neck, with the indicator where you have it. I am not sure what you are measuring with that setup, except possibly how round the necks are. The important thing is to determine if the neck is lined up with the case body. If you read off of the neck at the shoulder and then at the end of the neck, you can see if the neck is at an angle to the case body. Usually, I just do the measurement at the end of the neck.

 

[bigedp51]

Nice pictures.
On the last one, the usual setup for measuring case straightness is to put the support on the case body just where it meets the shoulder and to cantilever the shoulder and neck, with the indicator where you have it. I am not sure what you are measuring with that setup, except possibly how round the necks are. The important thing is to determine if the neck is lined up with the case body. If you read off of the neck at the shoulder and then at the end of the neck, you can see if the neck is at an angle to the case body. Usually, I just do the measurement at the end of the neck.

And sometimes you just grab any case and throw it in the Case Mastering Gauge to take a photo and get hung up on close up macro focus, lighting, and a shaking hands from drinking too much coffee and you forget why you are taking the photo in the first place. Thanks the "brain dead" photo will be removed from Photobucket and I promise not to pick my nose while taking one handed close up photos anymore. :-[

As a side note I ordered a Lee Collet die last night after driving myself nuts with two .243 RCBS dies and a Redding die. I had almost zero neck runout with the decapping-ball expanders removed with all three dies. I drove myself nuts trying to get near zero runout results with the expander buttons installed in the dies. I tried leaving the decapping rod loose, with an o-ring, dry graphite and normal lube in the necks and just kept scratching my head. I finally just went online and ordered the Lee Collet die, what if any secrets do any of you have with standard dies and case runout? I have a new .243 and the shooting range is calling me and I want to do some shooting before my collet die arrives.......help!

 

[bigedp51]

One more silly question.............


What do you have to do to make the stupid handle thingamabob "click" at the correct collet pressure. :

Sorry the Devil (BoydAllen) made me do it. ;D

 

[bozo699]

One more silly question.............


What do you have to do to make the stupid handle thingamabob "click" at the correct collet pressure. :

Sorry the Devil (BoydAllen) made me do it. ;D

Now I absolutly don't care who you are thats way funny ;D as a matter of a fact its the funniest thing I have ever seen on this site. Thanks for making him do it BoydAllen.
Wayne.

 

[bozo699]

Kenny,
I am sorry I just can't stop laughing my a@# off with the old style torque wrench with duck tape and string holding it on ;D Now no one is making fun of you, but it is right down funny. My wife hates this site(it takes time away from her) and she even had to laugh when I couldn't quit laughing she had to see what it was all about.

 

[TheOtherZilla]

One more silly question.............


What do you have to do to make the stupid handle thingamabob "click" at the correct collet pressure. :

Sorry the Devil (BoydAllen) made me do it. ;D

Now I absolutly don't care who you are thats way funny ;D as a matter of a fact its the funniest thing I have ever seen on this site. Thanks for making him do it BoydAllen.
Wayne.

I don't care who ya R. That there's funneee..

 

[bigedp51]

Kenny,
I am sorry I just can't stop laughing my a@# off with the old style torque wrench with duck tape and string holding it on ;D Now no one is making fun of you, but it is right down funny. My wife hates this site(it takes time away from her) and she even had to laugh when I couldn't quit laughing she had to see what it was all about.

Bozo699

One more crack about "old style torque wrenches" and I'll contact my AARP Legal Services attorney, and sue you for age discrimination.

All this new newfangled loading equipment and talk of torque wrenches is for sissies. I remember when having a firm grip on your reloading equipment really meant something.

 

[Kenny474]

That is seriously funny there

 

[bozo699]

That is seriously funny there

Yes it is!
On a serious note are you getting anywhere with the Kenny474,torqueomatic5000?
How do you plan on attaching the wrench?
Are you going to use anolog or digital,or mechanical breakover?
Wayne.

 

[bigedp51]

Did someone say something about the torqueomatic Jaw Breaker 5000??????

 

[ReedG]

Well, Kenny, your attempt at consistency has given some of us a chuckle. Don't take it personal. Trust me, though, take off the torque wrench, follow the instructions on the paper that came with the dies and you'll be all set.

I loaned a set of .22-250 dies to a friend years ago, who brought them back with the collet die "broke". He had put so much pressure on the handle of his Rock Chucker that it drove the innards of the die out through the top. I called Lee and they assured me that is a common occurrence. In fact, they are made to do that. The threaded insert is made of very soft metal and when an exuberant force meets an immovable object, the threads just strip and the top pops off.

It takes so little force to properly size the neck of a case that most people can't believe it. Take an old case or range pick-up and very carefully squeeze the neck with pliers. It takes nothing to totally collapse it, what can it take to squeeze it a couple thousandths?

With a collet die installed in a Rock Chucker so that the linkage cannot cam over, a good piece of brass can be neck-sized with barely more than the weight of your arm and hand on the handle. If you go very carefully, you will feel the collet make contact with the neck and then just the slightest more pressure on the lever you can feel the neck give. At that point, it is resized.

Due to the fact that the collet die sizes the neck against a perfectly straight mandrel, held in place by the depriming pin, I don't believe even a $400+ die of meticulously close tolerances can resize any truer than the Lee. It's the only method I've seen that "trues" the INSIDE of the neck. All other resizing dies form the outside and leave the inside to fend for itself. Another plus not mentioned here is NO LUBE!

The Lee Collet Die is true brilliance. I wish the quality control was a bit better sometimes, but there isn't a better way to neck size brass that I'm aware of. If they cost $250 or $300 most of the shooters would be using them, but it's embarrassing in the loading area to pull out a lowly Lee Collet Die.

 

[Kenny474]

I understand your point, but I think I will stick to doing things my way. It has further reduced my ES/SD, and my necks are more consistent then before by a measurable amount.

I also understand that a Rockchucker cams over, and hence this will do no good. My press that I use at the range does not cam over, and any inconsistency in force applied to the handle, be it less or more, creates variance in neck tension.

I plan to continue to do things as I have been, as I have seen measurable improvement.

 

[Nomo4me]

My Gramps said that 3 weeks into his Viagra prescription

I plan to continue to do things as I have been, as I have seen measurable improvement.