Trouble with Lee 357 seating die

[theMickster]

I was just about to seat some charged cases and found a big problem.
My charged 357 starline case will not fit into the seating die.
I thought I went too far with the expander die, but that is not the case.
Lee seat die: .380
Flared starline case: .383
It actually started crimping the bullet (.35995) before I was half way seated. I'm surprised I only noticed it now. I loaded 50 with it 2 weeks ago and had terrible leading. I think it swaged my bullets.
Is this Lee die too tight? Can someone measure a RCBS or other for comparison?
Thanks,
Mick

[462]

Several Lee seating dies were giving me the same problem, too. Got rid of them -- and the problems.

[Bullwolf]

I was just about to seat some charged cases and found a big problem.
My charged 357 starline case will not fit into the seating die.
I thought I went too far with the expander die, but that is not the case.
Lee seat die: .380
Flared starline case: .383
It actually started crimping the bullet (.35995) before I was half way seated. I'm surprised I only noticed it now. I loaded 50 with it 2 weeks ago and had terrible leading. I think it swaged my bullets.
Is this Lee die too tight? Can someone measure a RCBS or other for comparison?
Thanks,
Mick

I measured 2 of my RCBS seat dies from carbide die sets. An older and a newer one.

New RCBS seat die measured .384
My older RCBS seat die measured .386 so there even RCBS has some variance.

Measurements were taking using inside calipers.

You could probably send it back to Lee and just get a larger one, or even lap it to open it up yourself with a split dowel and some wet/dry sand paper.


- Bullwolf

[theMickster]

I'd like to open it up, but I don't have access to a lathe anymore. I think it would be hard to get the depth correct with a dowel/sandpaper.
Thanks for the quick responses and photos.
I love this place!

Mick

[Cherokee]

Mick - are you sure you have the die adjused correctly ? It looks like the ring is higher up the die body than I would think, but its hard to tell from the pic. I believe Lee includes adjustment instructions with the die set. I agree tho that the .380 mouth is tight, my RCBS measures .385.

[HiVelocity]

Mick-

I never use the seating die to fully seat the bullet and crimp with the same die, as is normally done. I use the seater die to simply "seat" the bullet only to a specific depth.

I use the FCD to crimp the bullet as a separate step (was recommended to me from a member here many years ago, works wonders and alleviates lots of problems.

Just food for thought,

HV

[Bullwolf]

Mick-

I never use the seating die to fully seat the bullet and crimp with the same die, as is normally done. I use the seater die to simply "seat" the bullet only to a specific depth.

I use the FCD to crimp the bullet as a separate step (was recommended to me from a member here many years ago, works wonders and alleviates lots of problems.

Just food for thought,

HV


I pretty much do the same thing when using a turret press, only I use the two RCBS seat/crimp dies pictured earlier. One is a dedicated seat die, and the other is a dedicated crimp die. (with no boolit seat stem installed)

When loading single stage using my old RCBS Rock Chucker press, I will sometimes dissemble one die and do it in 2 stages as well, or I can always reach for my already set up crimp only die. I try not to seat and crimp in the same step ever if I can help it.

I do have a Lee Carbide Factory Crimp Die (with a carbide post sizer ring) but I avoid using it as I often shoot boolits larger than .357 and my Lee FCD has a habit of sizing down my boolits inside the case during the loading process. It is not an over crimping or a die adjustment problem, but a side effect of post full length sizing the loaded round during the crimping stage.

You can easily see if it is happening by gently pulling a loaded round with a kinetic puller and measuring the pulled boolit with a micrometer. I know many others say it doesn't happen to them when they use a Lee FCD. My guess is all Lee Pistol FCD tolerances are probably not the same, and with different brands of brass thickness will vary as well. Perhaps my Lee FCD is just a tighter tolerance one. Either way I don't like to use it. Undersize lead boolits don't shoot very accurately for me, and tend to lead the bore.

If the Lee FCD works for well for you, heck keep using it. Just watch out to be sure it's not sizing down your boolits smaller during the loading process, especially if you change your components, or if you load for a gun that requires a larger (oversize) cast boolit than usual.



- Bullwolf

[bedbugbilly]

I'm wondering the same thing Cherokee is . . . can you not adjust the die higher in your press and adjust the seating stem to the correct seating depth you need? Does the die work on 38 SPL (if you load that cartridge?). The manuals show the 38/357 casing as .379. I use Lee 4 die set and don't have a problem but I've never measured the seating die. if your's measures .380 that does seem "tight" but if your flare is .383 and your die .380, how do you get it started into the die without binding? Have you tried not flaring the case so much or will your boolit not start if it isn't?

I also seat and crimp in two different operations and use the FCD. I know a lot of folks don't like 'em but I fortunately, have had no problems with swaging, etc.

It may very well be that the die needs to be opened up - or a replacement. You might give Lee a call and see what they say. If it is adjusted correctly, it sure sounds like the .380 is too tight and there ought to be more clearance than that. Good luck and keep us informed please as we can all learn from it.

[Larry Gibson]

Are you using the standard seating die or the Factory Crimp Die?

Larry Gibson

[JonB_in_Glencoe]

I was just about to seat some charged cases and found a big problem.
My charged 357 starline case will not fit into the seating die.
I thought I went too far with the expander die, but that is not the case.
Lee seat die: .380
Flared starline case: .383
It actually started crimping the bullet (.35995) before I was half way seated. I'm surprised I only noticed it now. I loaded 50 with it 2 weeks ago and had terrible leading. I think it swaged my bullets.
Is this Lee die too tight? Can someone measure a RCBS or other for comparison?
Thanks,
Mick
Mick,
I agree, I think .380 is too tight.
I'd take a photo like Bullwolf did showing the caliper dim.
then fill out the customer service online form on Lee's website and attach the photo.
Lee may just send you out a new die...or they may request you to send them the die for fixing or replacement?
Jon

[462]

"It actually started crimping the bullet (.35995) before I was half way seated

Because most seating dies are designed for jacketed bullets, the usual fat-for-caliber cast boolit gets swagged down. In your case, a cast boolit of almost .360" is being swagged by a die manufactured to seat a .357" jacketed bullet.

I have two Lyman .357 Magnum seating dies. Using an inside micrometer (a caliper will not give an accurate enough reading) their openings measure .383". Your die is too small.

[theMickster]

Thanks for all the comments and assistance.
I already loaded 50 about two weeks ago and had terrible leading. I may not have flared the mouths as much on the first batch.
I did a little experiment and took the lock nut off the expander on my Lyman M die for my .35 Rem and tightened it to the bottom. I then flared/ expanded a few cases. They came out at .382/.383 as well. That's why I don't believe I flared too much.
The last batch did have a little resistance to overcome while entering the seat die, but I managed o get them in there. These are my first pistol reloading attempts. Seems I have the proper equipment for the 4 rifle calibers I load, no problems there.
I will contact Lee and see if they'll do anything.
I've got a RCBS cowboy set on the way. I love the cowboy set for 45-70.

Mick

Edited to answer Larry ' s question: I'm not using the FCD. Seat and roll crimp with the Lee seat die.

[462]

"I did a little experiment and took the lock nut off the expander on my Lyman M die for my .35 Rem and tightened it to the bottom. I then flared/ expanded a few cases. They came out at .382/.383 as well. That's why I don't believe I flared too much."

Just measured a .357 Magnum case that was run through an M-die adjusted to expand the case to accommodate a .3585" cast boolit. Using a micrometer, the expanded case mouth (second step) measured .376". That .376" case easily fits into a Lyman seating die with a .383" opening.

Seems that, at least according to my measurements and what works for me, not only is your die too small, but the expanded cases are too big.

[theMickster]

462:
My virgin starline brass is .376 right out of the box. Far as I can measure, case walls are .009+.

Mick

[462]

"My virgin starline brass is .376 right out of the box. Far as I can measure, case walls are .009+."

Those numbers should give you an inside measurement of .358".

My Lyman sizing die sizes the outside of a case mouth .370" (second step) and .352" (first step) on the inside (too tight for my liking but I live with it). Measurements taken with inside and outside micrometers.

If you haven't, already, perhaps you need to start from the beginning and run a case through a sizing die and compare it to one that hasn't been sized. I haven't bought new handgun brass in eons, but always full length size new rifle brass.

My only experience with Starline brass has been with .44 Special, which has been excellent, and they do have an outstanding reputation for quality brass.

Suggestion: At your first opportunity, buy a 0"-1" outside micrometer. They can be had for less than $40. If you cast for rifle cartridges and are the least bit interested in neck tension and accuracy, an inside micrometer is indispensable.

[44man]

The most inaccurate .44's I made were from RCBS dies. Those with jacketed by the way. I won't even buy Lee dies. I use Hornady only now but did have one too tight for my larger boolits. The little seating stem is easy to lap and in a few minutes I had a perfect fit.
Other dies expanded too much or seated crooked so I had a bulge larger on one side.
The Hornady is easy to take apart to clean out any lube.

[kenn]

I'm wondering the same thing Cherokee is . . . can you not adjust the die higher in your press and adjust the seating stem to the correct seating depth you need?

This solution works perfectly for me. I've raised the die enough so it does not crimp at all and use a Lee FCD to finish up on the 4th step.

[44man]

EVERYTHING I load is seated and crimped at the same time. Never proven crimping separate is better.

[theMickster]

I'm just learning the ropes here and having a separate step made sense to me. I wanted total control. Tried it (FCD) with 3 rifle calibers with some good results and some bad. When I got my 45-70 I ordered the RCBS cowboy dies and use the seat and roll crimp in one operation with great success.
I will report back with any updates as to what Lee says and hopefully success with the 357 RBCS cowboy dies.
Thanks again for all the input, ideas, and civil discourse.

Mick

[44man]

Most of my Hornady dies came with a separate crimp die. Many of my boolits will not go through them from the top. No problem with cases but the top holes are too small. They try to seat the boolits.
They are called taper crimp but will do a profile. Adjusted right, they do a nice roll crimp but are best for the "J" things.
Seating and crimping at the same time is OK because as the crimp is forming the top of the brass has reached the crimp groove.

[MT Chambers]

This is the first time that I have heard of problems with Lee dies.

[44man]

This is the first time that I have heard of problems with Lee dies.
I can look at groups and tell you what primer you used and am close to telling you what dies you used.
Might sound crazy but what you do to brass counts more then anything. Look back and see how many times I said "brass is your enemy." if you see me with an "M" die or FCD, you know I lost my mind. Getting close enough at my age anyway.

[theMickster]

So the plot thickens.....
I contacted Lee through their customer service Web page yesterday. Today I received an email shipping notification from Lee.... for a decapping mandrel. WTH? Whatever!
Got the RCBS 357CBY set in today's mail. I proceeded to measure the seat die 's mouth. It is .386 and worked fine to seat and roll crimp my cases. I'll report back with accuracy and hopefully no leading.
I did notice the RCBS CBY expander is stamped .358. It measures out at .356. Lyman M measured at .357. I decided to make one myself a little more appropriate for fat cast boolits. .359. I'll try it out next time I load.

Mick

[theMickster]

I loaded 50 rounds with the new RCBS CBY dies. I used unsized, brand new Starline brass.
Lyman 357446 sized .3595.
Red Dot from 3.1 up to 4.7.
Accuracy was terrible at 25 yards. Perhaps I am not a good pistol shot off of a sand bag......
The good news is the leading was only light in the throats. None in the barrel!
This is a step forward.
A couple observations:
1. Unsized brass when loaded the way I did it is a slip fit into the cylinder. Cartridges hardly rattled at all.
2. A pulled bullet was only slightly under sized diameter. .358+

Mick

[462]

You say the new RCBS seating die swaged the boolits from .3595" to .358". Is that something you want? Do you suppose that may have attributed to the "terrible" accuracy and the "light" leading? Just asking, as none of my seating dies act as swagers, too.

[theMickster]

I can't really attest to the accuracy of my measurements this afternon. I will recheck when I get home from work. That's what I thought I saw. I was multitasking and may not have paid attention to what I was doing. I will make a more scientific test side by side with the Lee dies and measure before and after. I think my point was more to the fact that progress was made. :)