I reload for 30-06, 7.5x55 Swiss and .308.  I've used 168 gr. 308 FMJ Bullets in all three cases with good results. I just ordered a 170 gr. 308 lee bullet mold and a universal case expanding die to flare the mouth of my cases so that the cases don't shave the lead bullets as they are being seated. I'll need to order a factory crimp die to remove the flare and was wondering whether I can avoid buying three crimp dies by using a 308 factory crimp die which is the shortest of the three cases. Has anyone tried this and/or know of whether this will work?

I doubt that it will work without modification. The Lee FCD uses a collet to crimp the neck. The collet is activated when the bottom of the die contacts the shell holder.

I can only speak to 308 and 30-06, but, given the differences in case length between the two, you'll run into problems getting the collet to "activate" for the 30-06. To get it to work, you could probably fashion a cylinder that would make up the difference in length and would be placed between the top of the shell holder and the bottom of the die.

Maybe you could try a different method of crimping, like roll crimping.

I doubt that it will work without modification. The Lee FCD uses a collet to crimp the neck. The collet is activated when the bottom of the die contacts the shell holder.

I can only speak to 308 and 30-06, but, given the differences in case length between the two, you'll run into problems getting the collet to "activate" for the 30-06. To get it to work, you could probably fashion a cylinder that would make up the difference in length and would be placed between the top of the shell holder and the bottom of the die.

Maybe you could try a different method of crimping, like roll crimping.

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I believe the normal seater die will roll crimp if you back off the seating stem and screw it down a little more.
never tried it tho...

I reload for 30-06, 7.5x55 Swiss and .308.  I've used 168 gr. 308 FMJ Bullets in all three firearms with good results. I just ordered a 170 gr. 308 lee bullet mold and a universal case expanding die to flare the mouth of my cases so that the cases don't shave the lead bullets as they are being seated. I'll need to order a factory crimp die to remove the flare and was wondering whether I can avoid buying three crimp dies by using a 308 factory crimp die which is the shortest of the three cases. Has anyone tried this and/or know of whether this will work?

Lee sells the same crimp die for many different applications. My suggestion is to just try it. If it works you saved yourself some money. To answer your question I do not know for a fact if they are the same die but I would be willing to make an educated guess and say they are all going to be the same die. You might have to adjust the height of the die a little bit. But you may not even have to do that. Just adjust it with the adjustment knob.

BTW, I don't load for .308 but I load for 7.5x55 Swiss, 7.62x54R, etc. I also reload 30'06 in both bolt and semi auto guns. I do not crimp any of my loads as I find the neck tension after running through a sizing die is enough for the way I shoot. To keep from shaving the lead bullets I chamfer the inside of the case and I find I shave very little if no lead when I reload. If you don't chamfer you will shave a small ring. You might want to try it before you start flaring the case mouth and then having to crimp. You might find you still shave a very small amount. But usually I don't shave any lead or such a small amount it is not worth mentioning.

Let me know if you try it.

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I believe the normal seater die will roll crimp if you back off the seating stem and screw it down a little more.
never tried it tho...

This is just what I was thinking about  on my way to work just after posting my question.

Try your 308 seater die with the seater removed and run a 30 06
case in the die.  See if the die can "close" the case mouth.  If so,
think the 308 crimp die will work for the longer cases.

Good advice from everybody.  Inspector has good stuff to say.

Myself, I use a Lee loader to neck size and a lyman M die to put
a step on the case mouth for easy seating (for the bolt actions).
Use the seater die to seat and lightly touch the case mouth to close
the "step".  Just personal preference.  Gravitated to using .310 and
.311 sized cast for 308 and 3006 with softer alloy.  Not working the
case necks that much.

I imagine it would be difficult (but not impossible) with the different case lengths. Seems like you would have to futz with the die quite a bit to get them at the same level.

I doubt that it will work without modification. The Lee FCD uses a collet to crimp the neck. The collet is activated when the bottom of the die contacts the shell holder.

I can only speak to 308 and 30-06, but, given the differences in case length between the two, you'll run into problems getting the collet to "activate" for the 30-06. To get it to work, you could probably fashion a cylinder that would make up the difference in length and would be placed between the top of the shell holder and the bottom of the die.

Maybe you could try a different method of crimping, like roll crimping.

I stand corrected.   Please disregard my first post.   The 308 rifle factory crimp die won't work;  TooFew Pews explains it.   

Not sure why there confusions here. Yes you can it just crimps the neck, Just set it up like your reloading 308's. But watch your pressure if you crimp to tight it will cause increase.
davek42

I just read about using the full length sizing die (without the expander ball) to remove the flare from the mouth of the case after seating the cast bullet and tried a few on some .308s that I previously loaded. You can feel the case neck contacting the die as well as the resistance presented as the ram move the case further into the die. It takes a little finesse to get it just right but it seems to be working.  Does anybody know whether removing the bell from the mouth of the case using this method may not be a good idea? If it works, it will certainly save a few coin for all of the rifles that rifle rounds that I cast or plan to cast for.