Collet die vs full length

[Battis]

I bought a set of Lee collet dies for the 7.5x55 awhile back. I spent quite a bit of time getting some cartridges made - I couldn't get the neck tension to hold the bullets. I called Lee Precision and the tech told me to give the die an extra turn in the press to get it to cam over. It helped some of the time but I still had a hard time getting the rounds to chamber.

Yesterday I bought a set of RCBS full length dies. What a difference. The neck tension is perfect, every round chambers as it should, even with the bullets seated at slightly different depths (experimenting).
Either this Schmidt Rubin 96/11 does not like collet dies or I was doing something wrong.

[atr]

I have used the collet dies and you do need to turn down the die more to get more neck tension. I never had problems with chambering using the collet die system. Sound like you have a very tight chamber. I would suggest you take outside neck measurements of a case sized with a collet die and compare it to one sized by the RCBS. The OD of the collet die sized case may be greater than what your chamber can take.
hope this helps
atr

[462]

I have and use Lee's collet neck sizing dies for nine different rifle calibers, including the Swiss 7.5X55, and have never had any kind of problem. However, I ignore Lee's directions, and adjust the dies until a predetermined neck diameter is achieved.

I may be that, with your press, the die needs to be screwed in further.

[Battis]

I'm thinking it's User Error (mine) somehow. I can hand seat the bullets sized with the collet die, even with an extra turn of the die, but the FL die sizes the neck tightly. Also, I had to seat the bullets further into the case with the collet die than with the FL die, to get a round to chamber. Maybe the die just needs more turns into the press.

[Ben]

You can also take the mandrel ( the part with the decapping pin on the end ) out of the Lee Neck sizing collet die, mike it with an accurate micrometer and spin it with a drill and use some 320 wet dry sand paper and remove .001 from the mandrel.

Put it back in the die and repeat the sizing, by doing this in a trial and error sequence, you'll eventually end up with near optimum neck tension. ( don't remove .003 or .004 on your 1st attempt......Metal is much easier removed than it is put back on the mandrel. )

If you do make a mistake and remove too much metal & ruin the mandrel, Lee can have you one in the mail in less than a week and less than $5.00.

Ben

[enfield]

straight pull rifles are less forgiving to neck sizing only.

[UBER7MM]

Battis,
.
Collet or neck sizing dies only re-dimensions the neck. They leave the body of the case "as is", so that the case remains the same expanded dimension as your chamber. Having said that, one must first full length size and fire formed cases to your particular chamber before collet sizing those cases. Those cases are now meant for that rifle. I suggest you attempt to use your collect dies on fired cases.
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I'm not sure it that'll solve your problem of bullet tension, but it's worth a try. Let us know your results.
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I hope this helps,

[Battis]

The cases that I neck sized were fired from my rifle. I set the collet die up as instructed by the Lee directions, then neck sized the cases. I was kinda surprised that the was no resistance when I sized them. That's when I called Lee Precision and they suggested turning the die in further. I'll try turning it some more.
The writer of this article definitely does not like collet dies.
http://www.swissrifles.com/ammo/reload1.htm

[UBER7MM]

Battis,
.


Wow! Sounds like Lee wants to sell you their factory crimping die!
.


http://leeprecision.com/factory-crimp-die-7.5x55.html
.
(MidwayUSA lists them cheaper:)

http://www.midwayusa.com/product/533256/lee-factory-crimp-die-75mm-schmidt-rubin-75x55mm-swiss?cm_vc=sugv1625657


.
I personally don't own any Lee Collet dies. My neck sizing experience is from using RCBS neck sizing dies, in Mauser actions. I was taught that neck sizing is exclusively designed for single shot and bolt actions. Pumps, lever and auto loading repeating rifles need more play in the chamber and case to get them to cycle. (Having said that, I'm sure there's someone out there that neck/collet sizes for one of those types of actions with success. If that is the case, I say: "Bully for him.") Your Swiss straight action pull might fall under that category.
.
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I went to Lee's website to view their instructions for my self what they've got to say. It appears that you're not the first to have a bullet gripping issue:
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http://leeprecision.com/cgi-data/instruct/RM3512.pdf
.
TIGHTER BULLET FIT

As delivered from the factory, the collet die will grip the
bullet with a light press fit with cases of average hardness.
For a tighter fit, you can anneal the case neck or
polish the decapper mandrel .001 smaller. Do not go
beyond .001 smaller as there will be no increase in bullet
pull, and a decrease in accuracy as the bullet will then be
sizing the neck as it is inserted.

.

OPTION

The collet die provides the optimum bullet fit
for maximum accuracy and case life. Should you desire a
tighter fit, and are not able or willing to polish the mandrel
or anneal the case neck, you can order a custom mandrel
from the factory. Be sure to specify the caliber and bullet
diameter. Example: "Send undersize collet die mandrels
for 30/06 using a .308 bullet." There is a $5.00 charge.
.
I see your options as the one or more of the following:
1) Invest in a Lee factory crimping for about $15.
2) Buy the smaller mandrel from Lee, or as Ben mentioned earlier, you can modify yours yourself. As we all know, it is not uncommon to have to 'tweak' things in the reloading world to get them to work.
3) Scrap collet sizing and continue with full length sizing. The collet die has a money back guarantee. You can request a refund.
.
I might attempt the factory crimp. I own several Lee products and think they are a QUALITY AMERICAN MADE PRODUCT AND AN EXCEPTIONAL VALUE FOR THE PRICE. That in itself is rare today.
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(I do find fault with the strange rubber 'O' ring designed locking ring on their dies. I don't like the idea of adjusting a die every time one cares to use it. Just my humble opinion and easily remedied with a set screw style lock ring.)
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I hope this helps,

[Prospector Howard]

Ben is 100% correct. I use Lee collet dies on all my bolt action bottle neck cases. On every collet die I've bought, I had to take the mandrel out and use some 400 grit wet dry sandpaper and hone it down a thousandth at a time until the neck tension was right. Lee is notorious for things being the wrong size, like their push through sizers. They have really good ideas like the collet die, but nobody at Lee can read a micrometer.

[Doc Highwall]

I had to take the LEE die apart and polish the angle on the collet to smooth it up as it looked like steps requiring much more pressure to work, but I did not have to polish the mandrel.

[Battis]

I will try sanding down the mandrel slightly. That does make sense.

[ukrifleman]

I bought a set of Lee collet dies for the 7.5x55 awhile back. I spent quite a bit of time getting some cartridges made - I couldn't get the neck tension to hold the bullets. I called Lee Precision and the tech told me to give the die an extra turn in the press to get it to cam over. It helped some of the time but I still had a hard time getting the rounds to chamber.
Yesterday I bought a set of RCBS full length dies. What a difference. The neck tension is perfect, every round chambers as it should, even with the bullets seated at slightly different depths (experimenting).
Either this Schmidt Rubin 96/11 does not like collet dies or I was doing something wrong.

I use a Lee collet neck sizing die on PPU brass for my K31 loads with no problems. I load 150gn .308 S&B FMJ bullets and 155gn Lee cast bullets, gas checked to .309.
I run the cases into the collet die, then turn the case a 1/2 turn and run them through again.

I find this works well for me.
ukrifleman.

[Larry Gibson]

I spent quite a bit of time getting some cartridges made - I couldn't get the neck tension to hold the bullets.

If the necks are too thin or were not turned/reamed concentrically and they are tapered then the collet die will give that problem. The RCBS die won't as it sizes and expands completely different than the Lee Collet die. Load and shoot the cases after FL sizing with the RCBS and then clean them and try the collet die again. Could be they weren't formed quite enough when "made". If that solves the problem you are good to go. If not then you must determine if the necks are too thin or tapered. Lee's solution was the answer if they were too thin so tapered may be the problem. Neck turning or reaming to a uniform thickness will solve that problem.

Larry Gibson

[Battis]

I actually thought of FL sizing, then shooting and neck sizing.

I just loaded some dummy rounds using once fired brass. Some were neck sized, some FL sized. Each had the exact same bullet. Each OAL was exactly the same.
The FL sized cartridges chambered perfectly. The neck sized rounds took some effort to close the bolt.

[dromia]

I would check that the collet die is working correctly, I use the collet dies a lot with a variety of brass and have no problems when the dies are fettled. Lee's quality control is non existent so when buying their products you shouldn't expect them to work as advertised from the start.

Collet dies especially need fetling to get the best out of them and the main cause for issues is the mating surfaces between the collet and the sleeve being rough with tooling marks, unless these are polished out and lightly greased the sleeve and collet can jam together and at the worst collapse a case. If this is happening in your situation then the case neck could be bulging somewhat and the collet not sizing correctly, so just another thing to check. The collet should move freely in the die body.

Lee are probably the most innovative reloading manufacturer out there but they are let down by non existent quality control and poor materials, still they come in a ta price point that people like. So if you go the Lee route be prepared to fettle and or return to get their products to work as advertised.

[longbow]

I went the other way with the Lee collet dies ~ my .303 Lee Enfield has a typically sloppy chamber and bore so my RCBS dies were sizing the necks down too far for the 0.315" boolits I shoot. I had so much neck tension it was sizing the cast boolits down and the extreme sizing down then stretching up to suit fat boolits was hard on brass. I made a larger expander button which solved the sizing down of the boolits at seating but still wasn't doing the brass any favours.

So, I picked up a Lee collet die but wound up making a larger mandrel. After I posted my results I was told that the mandrel can be removed from the Lee die then the die adjusted to produce the neck inside diameter you want ~ larger or smaller than the mandrel. I am still using my fat mandrel but that makes sense since the collet squeezes.

In your case you could remove the mandrel then adjust the die to squeeze down a little more.

I agree with the advice given on full length sizing then loading and shooting to fire form to your chamber before you do anything else. The problem may well be that the shoulder or body has not been completely resized so is tight in your chamber.

I have three Lee Enfields that will interchange brass and one with a slightly tighter chamber that needs the shoulder pushed back a little bit more than the others. Brass will chamber but is tight.

Longbow

[Battis]

I took the mandrel out of the collet die and inserted it into the mouth of a fired case that I thought I had resized, and also into a fired case that had not been put through the die. The mandrel slid into the "resized" die with little or no resistance (same as the unsized case), which tells me that the die was not sizing the neck. I put it back together, screwed it into the press, and gave it three extra turns past contact with the shell holder (the Lee tech had told me to give it two turns). Bingo. I could feel it "cam over" and the neck was resized with enough tension to hold the bullet in place. Dummy rounds chamber perfectly.
Yep, user error.

[462]

Don't fall into the "user error" trap, when using Lee products.

I have learned that end-user post-manufacturing quality control, tweaking, and a disregard of their instructions is, more often than not, required in order for an item to operate properly.