Wasting your time with the Lee die. There's nothing you could want that the crimp function of a standard seating die won't do.

Two things to try: 

1) some actual crimp, sometimes it improves combustion
2) leaving enough flare to center the case mouth firmly in the chamber

I many years ago did just as you are doing. Bell the mouth just enough to get the Bullet to go in without shaving lead. Then seating and closing up the crimp at the same time, just enough so that I could chamber the round. Bullet was a 285 gr Lyman and with 18.0Grs of 4759 shot superbly. Problem became that with all that Belling and Crimping the Brass started to develop short little splits at the mouth of the case. Bothered me to the point that I found another way to shoot Breech Seating. You have to realize that at that time there was no supply of 38-55
available as there is now. Cartridge was discontinued and all that was left available was old Brass. When Winchester brought 
it out again I ordered 1500 rounds and then when I received it I found that Winchester being Brain Dead had shortened the length .050. And they would never admit that they had made a mistake. I have used it but have always been uncomfortable as I have since then acquired some really nice Schuetzen Rifles in 38-55 caliber. My answer has been to buy some really nice Tapered Bullet Molds and Load them by dropping the Bullet into the chamber and putting a charged case in behind and closing the breech. Works fine in all I have done it with when I find the appropriate powder charge. HTH Regards, FITZ.

If you want to spend a bit more $$, then the CH4D neck bushing die works great. The nice thing about the bushing die is you can change them for different brass (Win, R-P, etc.) as all brass is not the same thickness, and also for different calibers (I use mine for 30 thru 40cal).

Not to mention that any variation in brass length will result in different tension on the bullet when crimped = not good for accuracy.

Lot of different opinions all valid, here is another

I don't crimp my fixed 38/55's.  While it's possible Crimps do improve powder burn it not a issue with my loads. 300 gr bullet loaded long so it engages the lands on loading, complete combustion.  

If I was using the gun for hunting, had to carry cartridges in a belt or pouch & needed to extract a loaded round would probably crimp them.

Having said that my 25/20 & 38/40 cast loads used for NRA Lever Silhouette in Orgional Marlin 1894's run without crimps too. Sized with a neck sizing die the bullet pull is consistent & the hard to find brass last longer with minimal working of the case

Try running without Crimps, see a problem use the Crimp to cure it. Otherwise less you do better the result.

Boats

bnice, yes I use Pope bullets in 32-40 and 38-55. They are just right even in a Factory chamber. The last 1/8" of the Breech block closing seats the bullet with just a slight bit of engraving along the sides. And the Base on Pope cut molds is large enough so that you do not see light past them. So I have not needed any other method of seating. I actually do not consider what I do to Be " Breech Seating" but consider it to be "Shooting Loose Ammo". Has worked well for me shooting Offhand. My cases have a Cork wad to retain the Powder Charge, so I do not have to fuss about spilling Powder charges.
HTh Regards, FITZ.

If you shoot real light loads the case neck can smoke up because it does not expand to seal.  Little flare, enough to scrape the chamber works well. Opposite of crimping.

No single answer to the question, it depends on the load and how it's used.

Boats