Called Lee with a very simple question.

[dikman]

gg, that person must still be working there, sounds like the sort of run-around I got when I contacted them .

[FLHTC]

I have never seen taper defined on an engineering drawing as a % of anything.
It is normally defined as included angle, taper per inch in thousandths, a taper in rise over run - as in 10 to 1 but never as percentage.
You can reference ASME Y14.5M for the US standard for dimensioning and tolerancing drawings.

I made it all up.

[btroj]

There is a taper there. Having made a few Lee push thru type sizers I can tell you this- without that taper you need a bigger press. Pushing our little lead slug thru a non tapered sizer 2.5 inches long just isn't that easy. Learned that the hard way. Think of this, after pushing a bullet thru the sizing section the force required is greatly reduced. That is because the bullet has entered a larger section and is no longer being squeezed.
I make mine with some leade in taper but actually bore the back side out much larger. The leade in taper just needs to get the bullet started and centered. I like a larger initially taper than Lee uses as it makes seating checks easier, particularly if the check has been flattered at all.
Like others stated, the actual sizing section isn't that long, maybe 1/2 inch if that long.

[FLHTC]

There is a taper there. Having made a few Lee push thru type sizers I can tell you this- without that taper you need a bigger press. Pushing our little lead slug thru a non tapered sizer 2.5 inches long just isn't that easy. Learned that the hard way. Think of this, after pushing a bullet thru the sizing section the force required is greatly reduced. That is because the bullet has entered a larger section and is no longer being squeezed.
I make mine with some leade in taper but actually bore the back side out much larger. The leade in taper just needs to get the bullet started and centered. I like a larger initially taper than Lee uses as it makes seating checks easier, particularly if the check has been flattered at all.
Like others stated, the actual sizing section isn't that long, maybe 1/2 inch if that long.

Actually according to my measurement, it's .780 long, with a front opening of .367 and a finish diameter of .358. The length of the sizing area are all the same on my Lee size dies.

[btroj]

Thanks. I have never really measure the length but know it isn't the entire die length.

This short sizing section is good for us. It is the reason we can easily lap a Lee sizer to a larger diameter. If we needed to lap the entire length it would be far more difficult.

[EDG]

Without a taper you wind up with a shoulder with a corner radius for a lead in. All that will do is shave the bullet.

[JonB_in_Glencoe]

They either think I'm an idiot or the guy I talked to IS one. I suspect both. All I wanted to know is what taper their bullet sizing dies are cut to. Easy question and hardly a trade secret. He informed me that they make the dies by "pushing a carbide ball through them." So I asked how they achieved a taper by pushing a rigid sphere through a die body blank. His reply was "I don't know but that is information we don't give out." Apparently the wizard that they hired to violate the laws of physics holds his spell book very close to his chest. Sheesh!! Guess I'll have to just do the math myself. And start buying someone else's dies.

I would have just measured a Lee die.

[websterz]

With all the money I've handed them I didn't think it would be a big deal to ask. I guess I know better now. Oh well, the die is almost done, I just need to polish it.

[MBTcustom]

The Lee die has a sizing section .800 long, with a punch that is .850 long IIRC. The taper is such that it typically allows a bullet of .015 larger diameter to enter the sizing taper of the die.
The actual taper goes nearly the entire length of the .800 long sizing portion, with less than .100 parallel cylinder bore.
The entire length of the die is relieved often .015 or whatever drill size is closest to provide clearance for the bullets as they travel up the body of the die and into the container.
The rate of taper is not important. Usually, I taper mine from .005 larger than the bullets intended for it to a depth of .750, leaving me a parallel wiping length of .050.

[Ballistics in Scotland]

Yes, there is a taper in a Lee bullet sizing die. Yesterday I was pushing .431" diameter bullets through one of their .427" dies so I could size and lube them in a Saeco sizer with SPG for blackpowder. There is a definite lead in to the sizing portion of the push through die. The bullets came out of the Lee die at .427", and went into the Saeco .427" die perfectly, without any leakage from the soft lube.

I had to do this because the Saeco doesn't have enough leverage for one thing, and their dies don't have enough lead in to allow the bullet to size, but rather shaves lead. And yes, it was a Saeco mold designed for the .44-40 bullet, but drops them at .44 Magnum diameter, .431".

I didn't bother to do any measuring, since I was happy it worked and I had 1,000 bullets to work through........

Hope this helps.

Fred

Just guessing, but just because they are those sizes at the ends, doesn't mean that it is necessarily a taper. On hearing of the carbide ball, I thought "series of balls", rather like Parker-Hale used with ball burnished barrels (although I think they used hardened steel balls, and the value was somewhat reduced because it didn't affect the grooves.) It is possible that after pushing a graduated series of balls through, they then push larger ones half an inch to so from the lower end, and then push them back out again, producing a stepped rather than tapered bore.

[upnorthwis]

Here's my experience as a Process Engineer for 42 years. Supervisors don't know anything either. Only the operators and engineers know what's going on.

[mdi]

Seems the thread has jumped from bullet sizing dies to case sizing dies. Any kind of die that swages anything down in diameter has to have an "entry taper". The bullet needs a taper to start in the hole, just like a case mouth needs to be flared for a lead bullet to be seated. Basic metal forming 101...

[FLHTC]

Seems the thread has jumped from bullet sizing dies to case sizing dies. Any kind of die that swages anything down in diameter has to have an "entry taper". The bullet needs a taper to start in the hole, just like a case mouth needs to be flared for a lead bullet to be seated. Basic metal forming 101...

Where????

[mdi]

Where????

Around post 13...

[FLHTC]

If you say so

[Springfield]

FLHTC; Right here. Pretty sure bullet sizing dies don't have a sizing ring, only brass sizers.

"The actual sizer ring in a Lee sizing die is really narrow, like .010" or so, and there is a taper leading up to that part and another one afterwards. He is probably correct in telling you they arrive at the size of the die by shoving a carbide ball through the sizing ring to set it's final diameter."

[Avery Arms]

Not many companies are willing to give away their proprietary information for the price of a phone call. It isn't a huge R&D cost to buy their product and reverse engineer it.

LOL I don't think Lee has a lot of proprietary information regarding manufacturing a piece of steel with a hole in the middle of it, for one thing they can rarely get the hole the right size and the finish looks like they are using discarded drill bits as finish reamers.

[therealhitman]

I wasn't exactly asking for their secret blend of eleven herbs and spices.

Blimey! Made me spit coffee on me laptop!

[gwpercle]

And just why in the world do we need to know the Lee taper ?

[imashooter2]

LOL I don't think Lee has a lot of proprietary information regarding manufacturing a piece of steel with a hole in the middle of it, for one thing they can rarely get the hole the right size and the finish looks like they are using discarded drill bits as finish reamers.

Evidently they have enough that the OP was asking for it. You don't think Lee has an engineering design, drawing/model and associated cost in every product they make? Why would you expect them to give that away?