collet neck die AND neck tension

[cjmac]

So i was thinking . Lot of people like the lee collet neck size die . But how do you know what kind of neck tension you are getting? With a bushing die it is obvious.

 

[Toby Bradshaw]

Mike the mandrel. If you want a different diameter, Lee will send you one for $5. For my benchrest rifles I've always been partial to Harrell's FL dies and Wilson seaters, but for my .300WM hunting rifle I bought a Lee collet die and a Wilson seater (and a Redding body die to push the shoulder back). The mandrel that came with the collet die was 0.3054 and only gave about 0.0015 of neck tension with Barnes TSX (0.3078), which wasn't enough to keep the bullets in the magazine from moving under recoil, so I ordered a 0.304 custom mandrel (miked at 0.3038 -- pretty close!) from Lee to get ~0.003 neck tension. I have to say, I was a bit skeptical at first, but the Lee collet die works very well. Boyd has posted good things about the Lee die, and from what I can see, he is right.

P.S. If you mike the neck outside-to-outside before and after sizing, you can figure out how much the die is reducing the neck (including springback), and from there, what size mandrel you need. You can turn down the mandrel that you have if it's already close, using some fine grit sandpaper and a drill. But for $5, I just let Lee do the work.

 

[Erik Cortina]

Toby, you had me lost there for a while. It is "mic" as in micrometer, not "mike".

How is concentricity with the collet die?

 

[Toby Bradshaw]

Toby, you had me lost there for a while. It is "mic" as in micrometer, not "mike".

It's either. E.g., http://ecatalog.mitutoyo.com/Uni-Mike-Series-317-117-Interchangeable-Anvil-Type-C1115.aspx

How is concentricity with the collet die?

I just measured 8 loaded rounds, each fired twice. RWS brass, 180gr TSX. Four were <0.001 runout, three 0.001-0.002, one 0.003. Pretty good for such a long case.

 

[cjmac]

Yeah id say thats pretty good. Lee dies are so much cheaper to. Sounds like what im going with. Id love to have a set of Wilson dies but id have to get a arbor press girss im to cheap haha. Whats the deal with lees dead length bullet seat die ? I seen it on there site ... just curious

 

[Jay Christopherson]

How is concentricity with the collet die?

It's excellent - since your necks are being pressed against a mandrel, the inside of the neck is about as perfectly round as you can ask for from a neck sizing operation and IME, this translates to extremely low runout on loaded rounds.

 

[artbosco]

So i was thinking . Lot of people like the lee collet neck size die . But how do you know what kind of neck tension you are getting? With a bushing die it is obvious.

A phone call [262-673-3075] to a Lee Precision technician just verified that the collet neck sizing die is mechanically designed to give approximately .001" of neck tension.

If you want more ... you have to do some sanding.

 

[mikecr]

how do you know what kind of neck tension you are getting? With a bushing die it is obvious.

Actually, neck tension is never obvious. What you're referring to is interference fit. This is not the same thing as bullet grip (tension).
I know the common context of tension is simpler but I just think you should keep it in mind.

There is no tool on the market to measure tension. But for sure the easiest adjustment of it right now is length of neck sizing with a bushing.

 

[cjmac]

Thay say to use 25 pounds of pressure when sizing. How the hell do you when you are at 25 pounds. It has to be consistent. ....

 

[Hopkins]

The 25 pounds is more the minimum in that the result wont be changed with double that. If the neck is work hardened it will spring back so fresh or annealed brass will give tactile feedback during the collet compression.

 

[gotcha]

CJMAC, If you have a press with cam-over feature just set die depth for light cam-over. ( barely discernible) You'll be amazed with how little pressure is necessary to get uniform neck tension. You won't see those nasty smashed neck marks either. This will extend the working life of the internal parts of the die also. ........... Trying to approximate 25 lbs. pressure on cases from .223 to 30-06 just doesn't make good sense ???.................. BIGEDP51 has built a prototype torque gauge thing-a-ma-bob for His LCD's. Maybe he'll be kind enough to post pics

 

[BoydAllen]

The thing that you need to understand is that once the fingers of the collet have the ID of the neck in firm contact with the mandrel, there is no room for further movement. I say this as one who used to be a lot too much toward if some is good, more is better, to the extent that some of my cases ended up with ribs where the brass was forced into the collett's splits because of excessive camming at the top of the ram stroke. That was decades back, and as a matter of fact, the ammo shot just fine. I like to think that I am a little smarter these days.

 

[cjmac]

I still go more for the bushing dies but thay seem to have more run out and cost more. Id love a willson set of dies but thay require a new press. I think ill try LEE .

 

[cjmac]

So the amount of force is not a big deal ? So the die is only going to do as much as is going to on its own . Right?

 

[Hopkins]

Right!

 

[BoydAllen]

Using the factory method, look at the force suggestion as a minimum, not an exact requirement. Have you taken the die apart, to become familiar with how it works? If you have not, I suggest that you do, because they are unique, and it should help you reason out your moves based on knowledge of the mechanism.

 

[ReedG]

... and, if one needs to reduce the amount of the neck that gets sized, one can put a washer over the case of whatever thickness to get the resize you want. If you use and understand the Lee Collet Die, there is nothing better for neck-sizing cases due to the process it uses. Plus no lube!

 

[BoydAllen]

One more thing:
You can do a two step sizing operation with a collet die and a body die, and come up with some very straight ammo for those situations where unturned brass is used in a factory chamber. Some time ago I had mentioned this on this site, and got some favorable feedback on the comment from shooters who tried it. In my case, years ago, I found that when comparing the concentricity of rounds produced both ways, that doing the necks first with the collet die, and then the bodies, gave better results than the other way around. Of course I would encourage you to test this for yourself, and as always, to pay close attention to shoulder bump (measured from a tight case) when you set up your body die.

 

[Jay Christopherson]

One more thing:
You can do a two step sizing operation with a collet die and a body die, and come up with some very straight ammo for those situations where unturned brass is used in a factory chamber. Some time ago I had mentioned this on this site, and got some favorable feedback on the comment from shooters who tried it. In my case, years ago, I found that when comparing the concentricity of rounds produced both ways, that doing the necks first with the collet die, and then the bodies, gave better results than the other way around. Of course I would encourage you to test this for yourself, and as always, to pay close attention to shoulder bump (measured from a tight case) when you set up your body die.

^ This is the way I load ammo. Boyd's earlier comment on taking the die apart is also important - I've found the best results come when you take the time to disassemble the die and polish the surfaces that touch (collet fingers, die body).

 

[mattlewis]

I still go more for the bushing dies but thay seem to have more run out and cost more. Id love a willson set of dies but thay require a new press. I think ill try LEE .

An arbor press does not have to be something fancy and expensive with "Sinclair" written on it (no offense to Sinclair!)

Here's one from harbor freight for $38.

http://m.harborfreight.com/1-2-half-ton-arbor-press-3551.html?utm_referrer=direct%2Fnot%20provided

I'm no expert, but there are other benefits to chamber style Wilson dies. If you want to try them, here's a press on the cheap.