My Lee Seating Die Doesn't Seat

Reloading info for the 5.7x28mm

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My Lee Seating Die Doesn't Seat

Post by Pindon » 25 Mar 2023, 15:15

I bought the Lee dies for reloading the 5.7. The sizing die seems fine but when I try to seat a bullet using the seating die the case gets crushed and the bullet hangs up in the die.

What am I doing wrong?

Is it the sizing die or something else?

I am using my own Am Eagle cases that I once fired.

Do I need to but other dies?

Thanks for your thoughts.

Paul H.

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Re: My Lee Seating Die Doesn't Seat

Post by towerofpower93 » 29 Mar 2023, 03:04

Sounds like you have the die body screwed in too far and it's trying to seat and roll crimp at the same time.

I can't recall 100% if the Lee 5.7 dies are designed to have the option set and crimp in one step, but I know other calibers can.

This used to be in the instructions, but to negate the crimping/crushing feature, put a piece of brass on the shell plate and run the ram all the way up. Then back the seating STEM out a good bit and turn the die BODY down until you feel it contact the case. If you backed the seating stem out a bunch that's the crimp feature hitting the case mouth. Now back the die BODY out two full turns and secure it with the lock ring. Now bring the ram down, put a bullet on it, and run it up, adjusting the seating STEM until you achieve the desired OAL.

If that doesn't make sense I'm sure you can find YouTube videos covering it.

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Re: My Lee Seating Die Doesn't Seat

Post by lklawson » 29 Mar 2023, 04:46

My guess is that when you put in the Seating Die, you didn't back it out far enough. A lot of people will screw it in until it touches the shell holder and then leave it there, which crushes cases. Some won't back it out the 3 FULL turns and will back it out 1 1/5 turns by accident. Here's the Lee instructions.

The trick on getting the Lee die to seat the the proper depth and then also crimp is to seat as per instructions, by backing it out 3 full turns, then using the depth screw (top) to set the proper depth. Then, using the same cartridge, back the depth screw all the way out and then turn the seating die back in 1/8 to 1/4 turn in series, raising the ram each time, until the desired crimp is made. Then, lock the die in the press, raise the ram again, and turn the depth screw down until it it touches the bullet. Then done.

Lee Pistol Bullet Seating Die
INSTRUCTIONS: Raise the ram to the top of its stroke and hold. Screw bullet seating die in until it touches the
shell holder—then back it out three full turns. For magnum cases; back out bullet seating die an additional 1 ¾
turns. Lightly finger tighten the lock ring. Bullet depth is adjusted by screwing adjusting screw in or out to suit.
Bullets should be seated deep enough to work through the gun’s action. See MAXIMUM OVERALL LENGTH on
charge table. If crimp is desired, screw die in slightly; test until proper crimp is formed. Cases must be trimmed to
same length to provide uniform crimp. Excessive crimp causes bullet seater to deform soft nose bullets. This die
may be used with the Lee Automatic Bullet Feeder. It has a 45 ̊chamfer to allow for the mechanical feed fingers
and improved operator clearance. CAUTION Seating bullets excessively deep will reduce the case capacity and
increase the pressure. It is extremely important that full wadcutter bullets be used with light loads only. You can
select these by their reduced velocity.

Peace favor your sword,

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Re: My Lee Seating Die Doesn't Seat

Post by towerofpower93 » 30 Mar 2023, 02:34

Go with lklawson's 3 turns out instead of my 2. Been a minute since I've set up my Lee seating die, haha.

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Re: My Lee Seating Die Doesn't Seat

Post by MilesCadre » 03 Apr 2023, 08:30

Another bit i can contribute, but make sure youre champfering the inside of the case enough (dont go crazy now).. ive had that exact problem before, but with 45 colt and 357, and found i wasnt expanding the mouth quite enough. Happened with 30-30 too, and i now just add the step to my case prep. Takes a few extra minutes but saves valuable brass

For what its worth, my process using lee dies n reloading 5.7 are as follows

Soak the brass in hot soapy water for 30 min, then rinse and wipe it off. Let it dry
Raise the ram all the way up, screw in the sizing die until it touches the shell holder, then lower the ram and give the die about a 1/3rd of a turn DOWN. Be generous with lee sizing lube or hornady unique, both work well for me, then resize the brass.
Trim brass to spec (i do mine to 1.137), then deburr and champfer the neck
Soak in hot soapy water for 30 min again. Rinse, wipe off, let dry
Prime and seal the case
Charge the case
Raise the ram, then screw in the seater die til it touches the shell holder. Lower the ram, snug down the lock ring, then use a die wrench to tighten down (not super tight, but this screw the die down up to an 1/8th of a turn more). I then unscrew the top knurled nut about 1/4inch, and seat the first bullet. Ill progressively turn down the nut until the cartridge meets specified OAL. Ill then run a second round thru and confirm measurements, adjusting as needed.
Seal the bullet.

I have, but dont use, the factory crimp die. Havent seen a need to yet.. as for sealing, the bullets, iirc, are "glued" in on factory 5.7 ammo. As such, using markron primer and bullet sealer should help to mimic this trait i feel. As for sealing the primers, i have the sealant so why not?

I know my process isnt perfect and i imagine ill get alot of flak somewhere, but ive done this now for almost 80 rounds that ive put thru my m&p 5.7, and have yet to see any malfunction or ammunition issue..

My 2 cents anyways

EDIT: as for the double washing, this is to be gentle on the laquer coating, but also because the die set from lee is steel, not carbide. So i do my best to try and reduce wear and keep dirt out.. the second washing is to rinse out the primer pocket and wash away any brass flecks from the sizing, trimming, champfering, and primer pocket reaming (if i ream). Adds just a bit of time, but i feel it goes a very long way

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Re: My Lee Seating Die Doesn't Seat

Post by 67firebird » 01 Jun 2023, 19:45

First, make sure your shells are all properly trimmed to the same length. This is critical for a consistent crimp. With the ram fully up screw the die body in till it touches the shell holder then back out 3 full turns. This will result in about 1/4 inch gap between the shell holder and die body. Lower the ram and insert a properly trimmed shell. Raise the ram and screw the die body down till you feel it touch the top of the shell. If you lock the die body down at this level it will not provide any crimp. If you turn it down 1/8 of a turn it will apply a very light crimp (the die has 14 threads per inch, so 1/8 turn is about 0.0089 inches). If you turn it down to the point where the die body touches the shell holder and apply heavy pressure it will definitely make a mess. The seating die crimps by pressing down on the neck forcing it into slight cone. I use the factory crimp die which uses a collet to press in from the sides. I think that is better for bottle neck cartridges.

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Re: My Lee Seating Die Doesn't Seat

Post by Shotty » 05 Jun 2023, 16:12

If you follow the instructions from Lee closely, you will succeed quickly. The first sentence in the instructions is overlooked or misunderstood by many people. "Install a loaded round into the shell holder you wish to duplicate."
That's right, a loaded round. So if you are copying a SS197 round like I do, you use a S197 round to set up the bullet seating die. I myself did not do it correctly at first and it took some trial and error to stop crushing case necks.
I can also tell you not to bother trying to crimp the round using the seating die, you will end up moving the shoulder and or crushing the case before you even get a satisfactory crimp. I run them through the Lee factory crimp die and get a nice uniform light crimp.
On another note I had an idea about setting up a Lee 4 hole value turret press with two bullet seating dies and two factory crimp dies so each time you pull the lever it would alternate seating die then crimp die. A setup like this would save considerable time and be fairly economical to boot. ... DieSet.pdf ... auto-index

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Re: My Lee Seating Die Doesn't Seat

Post by panzermk2 » 06 Jun 2023, 06:39

Well for one thing the Lee seating die is not designed to be a combined seating/crimping die. RCBS likes to make a combines seat/crimp die all in one and they never work right. You end up seating then going back and crimping.

Also your very lucking to get your Lee dies to work. They have absolutely zero CQ and it's up to pure chance to get dies from them that work. they changed their sizing dies a few years back, for the worse, and their crimp dies is a nightmare. Took them 4 times to get me one manufactured right that worked.

I like your idea of running 2 up dies sets to seat and crimp.
Jay Wolf
Pr. Elite Ammunition

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