I like the taper crimp dies for my Winchester lever actions and some big bores, but what are "factory crimp dies" are these different than the standard roll crimp dies you get with some two or three die set?

This is a Factory Crimp Die, I don't know what you mean by taper crimp.

Ok, I now know what you mean by tapered crimps, I had to look it up and realized that I have one for 38-40 Win made by Redding.

I use the taper crimp dies on my 45ACP and 9mm. Regular dies roll crimp the mouth which is not good for cases that headspace on the mouth.

Lee factory crimp dies use a collet the presses into the mouth that is neither a roll or taper crimp. I use these on many of my rifles with good success.

I know of no taper crimp dies made for bottle neck rifle cartridges, nor see need for them; the bullets used in them all have crimp grooves.
Taper crimps are a recent invention for pistol ammo.
Lee factory crimp are not taper crimp.
Taper crimp is for bullets that don't or may not have crimp groves and for straight walls that can't be roll crimped.

Indeed; I use mine on my Dillon 650 when loading 45 ACP.

dpcd
Taper crimp dies are not something new, they go back many years, used in big bore rifles and double rifles and lever actions...I have a taper crimp for a 30-30 that I bought second hand some 50 plus years ago...Additionally they are made for most all pistol calibers and the only way to go IMO..the placement of a cannalure on crimped rifle bullets is seldom in the right spot as Im sure you know, the taper crimp needs no cannalure.

They are absolutly the best crimp for any lever action tube loaded rifle, and heavy recoiling calibers in that they simply squeeze a taper on the neck and avoid that bulge that one gets from time to time because we use rotary case trimmers that dont' have that degree of accuracy to get all cases the same other than the file trim die which is accurate but a slow process..I feel the taper crimp die is needed on DG rifles, especially doubles..Good insurance at a cheap price as they cost only $15. give or take and you really should try one, you might like them.

Pierre van der walt has a interesting chapter in African Dangerous Game Cartridge including their custom made Taper dies they had made some many years ago by Lee for their big bore and double rifles.

Get on the internet and type in Taper crimp seating dies, they are made by Lee, RCBS, Forester, in fact most die companies have made them for years until recently of course, today they are not making much of anything..

Micincolo,
Would you entertain selling those taper crimp dies for the 38-40 win?

I lost or sold my old taper crimp 30-30 die, so did get another one ordered and delivered..so now just need a 38-40 and 25-35..Im on notify form Brownells Midway and Graffs, the wait is on,hope to hell I live that long!! Bett'em it will be a horse race and a change of presidents hopefully to Republicans.