a little confusion on seating die....

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huskydriver

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I'm new to reloading and have been having a little confusion to the Lee seating die and use of the factory crimp die. My first batches of reloads were showing a definite bulge at the mouth where the bullet was seated. Does the seating die also put a crimp or taper to the round? I've also got the factory crimp die. I've set it up each die per the instructions. I thought I saw a video on youtube that you can actually take the crimp or taper out of the seating die and only use the factory crimp die. Is this a correct procedure.
 
The seater has a crimp built in. It can be adjusted to seat and crimp, or just seat. (Or just crimp) The FCD also crimps, but has the carbide insert which "post sizes" (The ring is larger than the sizer though, has to be), and "irons out" any bulges etc that might stop the round from chambering. Some think this is a good thing, and some think it irons out (hides) problems that should be fixed before it gets to the FCD.

Some IDPA guys use it to ensure all rounds feed and fire, instead of checking all their rounds with a case gauge or barrel. It will do that.
 
Is this for rifle or pistol? Some Lee sets come with a Dead Length Seating die which does not crimp. If it's a rifle set the crimp die doesn't have the carbide post sizing ring.
 
I spoke with an RCBS tech, because I was having the same bulge problem with about 5% of my reloads. He said that the crimp we see on factory ammo is actually way overcrimped, and to back off on my seat/crimp die, till I could just barely see the crimp. That sez he, is a proper medium crimp! I mostly seat and crimp in separate operations.

For cast semiwadcutters, I adjust the overall length so the case mouth leaves no gap between it and the top crimping groove, then adjust the seater so the case mouth is just flush with the outside diameter of the bullet, leaving no lip to hang up, and a minimum place for dirt and other nasties to enter. Cured most of the problem, although due to differing case lengths, (I hate trimmming cases!) I use my Lee Factory Crimp Die every so often. Solves the problem handily. :)

On plated bullets, I lightly chamfer the case mouths, then I use my Dillon seater, which does both a taper and roll crimp, and use very little crimp or taper...just enough to move the case mouth against the bullet so I don't cut the plating.

Jacketed, I crimp lightly into the cannelure,and don't worry about OAL. I've never had a problem with "bullet pulling". (YET!:D )
 
Thanks for asking our advice. Welcome to reloading.

huskydriver said:
I'm new to reloading and have been having a little confusion to the Lee seating die and use of the factory crimp die. My first batches of reloads were showing a definite bulge at the mouth where the bullet was seated. Does the seating die also put a crimp or taper to the round? I've also got the factory crimp die. I've set it up each die per the instructions. I thought I saw a video on youtube that you can actually take the crimp or taper out of the seating die and only use the factory crimp die. Is this a correct procedure.
Click to expand...
What chambering(s) are you loading?

It makes a HUGE difference.

Lee FCD for bottlenecked cases is different from the Lee FCD for straight-walled cases

For straight-walled cases, there is also different considerations for cases that headspace on the case mouth and cases that headspace on the case rim.

Which have you got?

Lost Sheep
 
FYI, I'm loading 9mm Berry's 124 and 115 RN plated bullets with once fired brass. I have the Lee Classic Turret press which came with the deluxe four die set which included the factory crimp die.
 
Learn to Get Dies Properly Adjusted

First thing as a new reloader is to read lots of info from good reloading manuals. They are all slightly different, and reading several of them can give you tons of great info.

Do no overwork your brass. Bell the case mouths only the minimum needed to allow the new bullet to start to enter the case and stay in place before you seat the bullet.

For rimless calibers, be very careful to only adjust the seating/crimping die to provide the lowest level of taper crimp needed for the particular reload (to withstand bullet pull during recoil or setback during feed). Unless you are loading hot loads, this is not much.

Finally, understand the real purpose of the Lee Factory Crimp Die. It is simply to do a final resize on a loaded round to make certain it meets all original factory specs that will insure it reliably feeds and chambers in all guns. During this process, the post sizing can and does fix numerous slight problems with a reloaded round, such as a bullet that is a little crooked or a case slightly bulged. But if you learn how to do your job well, you will not have those problems to fix!

If you are loading range brass, you might find some problems with a few rounds not properly chambering in your guns (especially common in .40 S&W) - the Factory Crimp Die is the perfect solution to this. But if you are reloading only brass that has already beef fired in your gun, you should never need it.
 
the post sizing can and does fix numerous slight problems with a reloaded round, such as a bullet that is a little crooked or a case slightly bulged.
Click to expand...
It can iron out the bulge, but won't straighten the bullet in the case, or did you mean round.
 
Adding to Mauser69, expand and bell as little as possible. Then, on 9mm I taper crimp only enough tobe visible. Doing that accommodates varying case lengths with the long cases receiving a tad more crimp while the short cases retain a very small flair.

IIRC you can set the FCD for a very small roll crimp, which should work.
 
Don't crimp with the seating die, crimp with FCD

The instructions that come with the Lee Deluxe Pistol Die Set for the seating die explain how to set the die so that it can be used for seating only or for seating and crimping. If you are using the Factory Crimp Die, you should adjust the seating die so that it does not crimp and crimp with the Factory Crimp Die. I read this somewhere in Lee's documentation.

I have my FCD set for a light crimp as I am using Berry's plated bullets and Berry says that the crimp should not deform the bullet for best accuracy.
 
The "crimp" fan an auto case like 9MM should just remove the bell, or maybe .001 more, as it headspaces on the case mouth and neck tension holds the bullet.

Using the seater to crimp 9MM, or adjusting it to seat only and then crimp separately with the FCD will both produce satisfactory results.
 
As stated above, a slight bulge is O.K.

Look to see if the bulge is even all the way around or heavy on one side and slight or non existent on the other. This would indicate the bullet going in crooked.

Do the "plunk" test with the ones you have questions about. Get a max case gauge or take out the barrel of the gun you are going to be using these in. If the drop in and out without any effort, they should be fine.

Another thing to look at is your mouth flare on your resizing die. If you don't get enough flare (just the right amount) on the case mouth, it can cause or magnify this issue also.
 
The "coke bottle" appearance is perfectly normal, but IMO, your rounds kind of appear unusually bulged. It actually looks like the case mouth isn't touching the projectile.

Could be you are over belling, in which case it can create an excessive bulge even after crimping.

GS
 
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