Looking for advice on using Lee Collet die with Forster CoAx

[Mike402]

As title says, I'm using that combination to size necks. I originally set it up to size at the end of the stroke, but I am seeing small marks on the neck, and I have even scored the inside of the die, clear indications I am using too much force.
I tried backing it out and going by feel, but I notice some necks get sized and others don't. I would like a consistent process where I don't have to check every time.
Lee says roughly 25lbs. Has anyone come up with a way to measure that consistently? In my search, I found a torque wrench adapter that fits the Lee press, but nothing on the CoAx.
Has anyone rigged a system that addresses this issue? Also if anyone is using this combo, how did you set up it up to work with the CoAx? Sizing in middle of stroke or after cam over?
Thanks in advance!

 

[clowdis]

I'm sizing in the middle of the stroke and haven't had any issues. The marks on your necks may be from where the fingers join to form the neck.

 

[GrocMax]

It helps to polish and lube the die parts in the tapered sections. As previously mentioned set it up so it bottoms out on press lever mid stroke, stay away from the cam-over point.

 

[JohnKielly]

I would think that the Forster press would be about the last device I'd choose to use a Lee collet die with. It's functionality, floating the die, would mitigate against the die being adjusted for best effect. Have a look at what John valentine suggests about collet die adjustment:


Using The Lee Collet Die.
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 poilishing 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 noticable 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 draging effect . Normally you dont 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.

 

[Mike402]

I have polished the internals and applied grease. It sounds like the mistake I was making was setting it to cam over point. I have actually ordered new collet dies and will set up to size mid stroke as suggested. That still leaves me with needing a constant force indicator.

So nobody has seen/heard of a torque wrench mod that provides this? I called Forster and they said that past customers have inquired about this very thing, but they unfortunately couldn't give me a solution. Their advice was to go to forums like this and ask there...

 

[Trevor60]

The article by Valentine is excellent information.

I would kindly disagree with John on the co-ax being a poor choice. For me it is the opposite i think it is an excellent choice.

I set my lee die to size at the bottom of the stroke. for 308win my lock nut is 7 threads from the bottom. This give me complete travel and consistent stop.
The lee die is easy to use and adjusting it with the co-ax makes it seconds to change to get the right amount of feel (tension) on the neck.

The only thing i would add as a (should do) is to cut a sliver of masking tape and place it on the top of the die have the tape line up in the same direction with the slit in the lock nut, that way you can watch to make sure the lock nut hasn't come loose and it gives you better indicator when u need to adjust the die to tighten or loosen.

GrocMax stated it first you may want to polish the fingers. or add some hi pressure grease to the fingers for smoother operations.
The lines you see have no affect on the brass, they are cosmetic.

All the best
Trevor

If you were truly over pressuring the die the aluminum body would strip and you would pop the top off the die. The die doesn't touch the sides of the case as it is a neck die. the neck portion runs up into the collect and squeezes the neck.

You could take some steel wool and polish the mandrel to smooth everything.

 

[savagedasher]

I think it the best press ever .
My shed has many others in it.
But for it to work correctly it must cam over .
Larry

 

[JohnKielly]

Don't know about over pressure blowing the top off dies, but I have all the mandrels & more that I need that I've recovered from dies donated to me that would not disassemble any more because the bottom of the lower unit was peined over & the collet irrecoverably stuck in it's mating taper. That's allowed me to polish the mandrels to other diameters as needed.

 

[Mike402]

Don't know about over pressure blowing the top off dies, but I have all the mandrels & more that I need that I've recovered from dies donated to me that would not disassemble any more because the bottom of the lower unit was peined over & the collet irrecoverably stuck in it's mating taper. That's allowed me to polish the mandrels to other diameters as needed.

That is exactly what is going on with my dies. Haven't popped the top off, but "bottom of the lower unit was peined over " is what I'm seeing. I was able to disassemble and polish, but it is scored and gets stuck again after about 100 rounds or so. I have to regrease pretty often. With the cost of the dies, I decided to buy new ones and get them set up correctly this time.

 

[Mike402]

So quick update to this thread. In my research I came across the "Consistent Crimp" from Titan Reloading. Exactly what I was looking for (a repeatable torque solution), but unfortunately they don't make an adapter for the Co-Ax. I decided to pick up a Lee Classic Breech and throw it all on an Inline Fab plate, so I can switch it out quickly. Yes, I bought the press solely for sizing necks, but I'm loving it, as there is no more guessing how much force I am using. By the way, its shocking how little force 25lbs is on a press handle.

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[jepp2]

Just offering my opinion. The use of a device that limits the torque to a specific value is an unnecessary complication. My experience also differs from that offered by John Valentine.

I have many Lee Collet dies as I find them to be excellent. The produce case necks with less than 0.001" TIR always. No case lube is necessary.

I set my dies up exactly like the Lee instructions define. I used to use an RCBS Rockchucker now I use a Redding Big Boss. Since both presses cam over, I screw the die down until it touches the shell holder on the raised ram. Lower the ram and screw the die down 2 more full turns (sometimes not possible with the Redding due to the opening size). From there it is all by feel. The estimate of 25 pounds force is probably pretty close, but not worth worrying over. After you use the dies for a while, you can feel the neck compress against the mandrel. Necks are always sized correctly. I also do as they suggest turn the cartridge 1/2 turn and size a second time. This time you will not feel the case compress.

I used to have to polish the mating surfaces as they came pretty rough, but the last several purchased more recently are much better finished. I do lube the mating surfaces, but it isn't required that often.

I have never popped the top off the die, or done any damage to the internals. None. But do not operate the die without a case in place or you can collapse the fingers. If you do, just spread them with a phillips screwdriver. I have sized 10's of thousands on Collet dies. I do anneal every 5'th firing, so I don't get into issues with spring back of work hardened brass.

Just for reference I am including a picture (courtesy of Clark on TFL forum) showing how poorly finished the mating surfaces were at some point in time and how they look after polishing. If yours are rough like the top picture, you do need to polish them or they can gall even if lubricated.

[URL=http://s860.photobucket.com/user/jepp2/media/260Leecolletdiecolletandcolletslevebeforeandafterpoishing.jpg.html][/URL]

 

[clowdis]

That still leaves me with needing a constant force indicator.

I don't understand your need for a constant force indicator? It is a metal to metal crush and when you hit bottom....that's it! You're not going to "overcrush" it. Just press until it stops, you'll feel it when the neck resizes.

 

[pete1955]

You have a fantastic Forster press that allows the die to float and self center. That works great with Forster full length benchrest dies with the high mounted floating expander that greatly reduces and even corrects neck runout.

So why use a cheaply made Lee collet die that needs polishing and makes you wonder if you pulled the press handle hard enough.

Hold it, I found your answer in Google images.........duct tape and string.

/

NOTE, pull until you reach 25 pounds or until the duct tape rips and the string breaks.

(or buy a real die and let the press cam over)

 

[savagedasher]

You have a fantastic Forster press that allows the die to float and self center. That works great with Forster full length benchrest dies with the high mounted floating expander that greatly reduces and even corrects neck runout.

So why use a cheaply made Lee collet die that needs polishing and makes you wonder if you pulled the press handle hard enough.

Hold it, I found your answer in Google images.........duct tape and string.

I don't think with a compound increase that camover gives that the tool would have any accuracy effect. Foot # is not done that way in automotive. Larry

 

[pete1955]

I don't think with a compound increase that camover gives that the tool would have any accuracy effect. Foot # is not done that way in automotive. Larry

1. Did you notice we are in a reloading forum and not a automotive forum.
2. Do you understand what a joke is or do you use duct tape to fix your car.
3. Are you a Canadian and drive a K-Car convertible?

 

[savagedasher]

1. Did you notice we are in a reloading forum and not a automotive forum.
2. Do you understand what a joke is or do you use duct tape to fix your car.
3. Are you a Canadian and drive a K-Car convertible?

Not really but I know When you use a torque wrench It is base off a 1 -1 ratio And a cam over press it is not 1-1 ratio .
Larry

 

[pete1955]

Not really but I know When you use a torque wrench It is base off a 1 -1 ratio And a cam over press it is not 1-1 ratio .
Larry

Thank you, I'll try to forget that the next time I put a crows foot or a dog bone extension on my torque wrench.

 

[Mike402]

I don't understand your need for a constant force indicator? It is a metal to metal crush and when you hit bottom....that's it! You're not going to "overcrush" it. Just press until it stops, you'll feel it when the neck resizes.

I have to disagree with you on overcrushing it. I definitely overdid it camming over with my forster press. I had 'score' rings above the collet fingers and they would get stuck inside. Polishing and greasing them helped, but I was simply using too much force. I have now resized a few hundred cases with the new setup and new dies, and don't see any of these marks. Yes I suppose it can be done by feel, but it just makes me feel better for consistency's sake that I am resizing each piece of brass with the same exact force.

 

[clowdis]

Anybody ever read the set-up instructions that come with a collet die? Anybody? And where does it say to cam the lever over? In fact it says specifically not to cam the die over or you will ruin it!

 

[Hondo64d]

I like the cam over method and is all I do with my collet dies and I use them in a Forster press. All I do is change the lock ring to a Forster or other that will work in the Forster press. Lees instructions are to prevent folks that don't have a brain from damaging their die. If you are careful, the cam over method works great and is as consistent as you can get.

To set it up using the cam over method, run your ram to the top of the stroke and screw the die in until it touches the shell holder. Run a case in into the die, going all the way to the top of the stroke. Check to see if the neck is being sized sufficiently. If not, screw the die in a little more and try it again. I'm talking very small adjustments here, no more than 1/16 of a turn at a time. If at any point, I feel the pressure required on the handle required to cam it over is getting too much, I quit adjusting the die down and instead polish down the mandrel a little at a time by chucking it in a drill and using Emory cloth.

This procedure has worked well for me on every Lee Collet Die I have and I don't have to guess that I am using the same amount of pressure on the handle every time.

John