Busted Lee Neck sizing die

[tufrthnails]

So I was reading directions and seen that they suggested screwing die in to touching shell holder, then screwing in 2 full turns if you have a cam style press like my RCBS. They did say you would need around 25 lbs of pressure so I decided to try it that way well my idea of 25 ft/lbs and theirs must be different. After pretty nasty bang I realize the whole top of die was pushed out of body now I wasn't putting very much pressure on it. So my question is do you guys do the one turn and let the press cam or the 2 full turns and "feel" the sweet spot?

[jonbearman]

None of the above. I use a hornady tool to measure off the shoulder and carefully (a little at a time) adjust the die down to bump the shoulder .002 thou so the cartridge functions in the gun with no pressure on the bolt handle to close it.It should close smoothly with no tension. I have not read there instructions as they are only general,2 full turns is way too tight. At best the die should be only touching. If this is a collett die then you are way off. You need to reread the instructions as there may be different sections in the pamphlet for different types of dies. Call Lee and they will replace the die and talk to a technician till you get the right imfo on how to ues a collett die properly. I am sure there is someone on here who will chime in with an easy way to set it up.

[darkker]

Problem with the cam style presses, is you don't get a "feel" for the pressure being applied. I do the recomended turn set-up.

[foxx]

I really like the Lee Collet Neck Sizing Dies with my RCBS press, but I do not do it the way they say (turn the die deeper so as to not use the full cam-over stroke of the loding lever). Instead, I turn it down so that it does not quite squeeze the neck down when the lever is all the way down... then, I turn it a little more, test it, then a little more, test it, then again untill the die will size the neck just enough to hold the bullet without allowing it to slip under pressure. I don't worry about a "feel", I just use the full stroke of the lever. Once I am there, I keep it there. When I am done, I remove it from the press making sure I don't turn the locking nut, and then, the next time I use it, I back it off from that spot a little and repeat the above to confirm. Have never had a problem.

[seanhagerty]

I have a torque wrench I put on my press for things that require a specific amount of force. Never busted a die that way. 25 ft lbs isn't that much btw.

[gotcha]

When you get your new threaded cap try this: ...... Insure the O-ring between cap and body is fully compressed. Turn die into press until it touches shell holder plus one full turn. Measure diameter of case neck before sizing. Put case in shell holder and pull handle using "medium" pressure. Now measure diameter of neck again. This measurement is the maximum amount the neck can possibly be compressed. Now, with same case in S/H, back the die out of the press in small increments until you reach the point that the press barely cams over. Insert a fresh case and size. Check neck diameter to insure maximum sizing. Now set lock ring so its partially compressed. You're good to go! ................ The main idea here is to use as little cam over as possible since caming over puts extra wear on press linkage. ......... The cam over "set point" can be locked in by using a Forster style lock ring. I use these and have seen no difference in neck run out.........Oh Yeah. Cam over provides consistent minimal pressure so you don't need a torque meter in your elbow. :) ....... BTW as Sean Hagerty says, You'll be amazed how little pressure is necessary

[bflee]

If you are bursting dies you are doing something way wrong! I havnt been reloading but about two years for 308, 6.5CM, and now 260, but it requires alot of force to burst a die. Try doing things a little at a time and check and recheck. I find with the Lee's if you pull the lever down and screw the die down with just a hair of tension it works great. I am not a benchrest shooter by any means as I only reload so I can shoot cheaper, but I can shoot under 1/2 moa out to 700 yards and I did stay at a holiday inn express last night!

[Fenrir]

If you set it up this way you will never bust another die.


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 its 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 can’t 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.
This is not a 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 utilize 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.

[LongRange]

With the ram at full stroke screw the die in until the die bottoms out on the shell holder then size a piece of brass and check it...if its not were you want it turn the die in 1/8 to 1/4 turn and size a different piece of brass and check it....keep doing this with a different piece of brass until your where you want to be.