The UK's Finest Independent Forum for Shooters and Gun Owners. Est 2010.

Lee .357 TC Die set.
The expander die sticks when the press is at the top of its stroke - I mean sticks. It's a two handed job to pull the handle up and the bench lifts off the floor! The upward stroke feels fine. The other dies seem fine.

Also, the die is virtually touching the shell holder before I get sufficient expansion for a cast bullet to start.

Taking the die apart, the exapander plug measures .355" up to .376". The surface finish of the plug I would describe as rough. There is an accumulation of brass shavings. At the extreme of the chamfer you can feel machining ridges with your nail.

A final observation, the plug seems free to move up and down inside the die by about 3/16". The only thing holding it in is the screw component for a powder measure. Is this correct - should the plug move?

Bullets measure .357"

Options?
1. Emery/lapping paste to smooth the od of the plug?
2. Some form of lubrication - possible powder contamination?
3. RCBS or some other die perhaps would be less bother.

Ideas?

In another post on the dangers of reloading I said

"NEVER force anything in reloading - the leverage on a press is massive if it ain't working something is wrong - STOP."

First QUESTION
What press are you using - I am assuming it is a Lee progressive - based on the powder discharging system working through the expansion / .357 cartridge
Sometimes the binding is somewhere else (ie sizing die)
What sizing die are you using - is it carbide - do you lubricate (eg spray the outside of the cases)?

THIS IS THE PROBLEM
"There is an accumulation of brass shavings. At the extreme of the chamfer you can feel machining ridges with your nail"
you need a smooth surface that slides - it is the increasing size of the plug that does the work and expands the case neck

QUESTION 1 Your option you mentioned were and without seeing die (but as per statement above)
1. Emery/lapping paste to smooth the od of the plug?
YES do this first - you want it very smooth

2. Some form of lubrication - possible powder contamination?
I did not exactly understand the line
I initially assumed/decided that you were trying to say that you thought that the powder residue acts as a "gripping agent" and should you add a lubricant?
YES Make sure your put Imperial Lube on the Expander This is wrong on a progressive press.

I believe this is the correct process... in the case expansion step pistol / revolver cases you need to be careful of lubricant since it catches the powder that is dispensed with the powder dispenser. Hence the need for very smooth surface and minimum depth expansion!

Remember that the case neck expansion has two primary purposes
1. To widen the case mouth to allow the bullets to be pushed into the case without lead shavings marring the end product
2. To act as a small ridge to hold the bullet in place and aligned as the progress press indexes / moves to the next station to seat and crimp the bullet!


NOTE
Only expand the case a small bit past the minimum you can. (remember : Revolver / pistol cartridges shorten over the reloading cycle)
Working the brass too much will make the case necks brittle leading to case necks spilts and reduced neck tension.

QUESTION 2
"the plug seems free to move up and down inside the die by about 3/16". The only thing holding it in is the screw component for a powder measure. Is this correct - should the plug move?"
In my experience it could move to a point - then it hits a "stop" - to become a FIXED object expanding teh case (think of your FL resizing die)
The movement is to help centre the case since often the case is unsupported

LAST TIP
Every 200 / 300 rounds take your bullet seating die apart and clean it - the inside and the seating stem.
Depending on the lube - you may find that small amounts of lube get pushed up onto the seater stem - its is compacted and the nett effect the bullet get pushed deeper than than the die is set - think of a LUBE SHIM!

Simple cure: use a Q Tip to lube the inside of the case neck before resizing as well as the outside.
Was the cases aftersizing to clean off the lube.

As above clean thoroughly and polish smooth. Lee kit comes at a price point and as such their finish and QC leave a lot to be desired, most Lee kit will need a bit of fettling to get it to work as advertised.

How much flare are you getting on the case mouth? It could also be that the case die is set too deeply the flare should just be perceptible to the eye, no more.

How clean are the insides of you cases, do you tumble/clean them everytime they are fired? Fouling can and will build up on the inside of a case and also cause binding.

Lubing to get it to work is not a good idea as that is just elastoplasting over what is a mechanical problem that needs addressing.

Personally I've never got them to work satisfactorily for me and I always use a Lyman "M" type expander die.

The expander plug should be moving up and down against the top nut, the reason it is free floating is you will need this feature if you ever choose to use their case operated powder throwers. Their auto disk measure is one of their better pieces if kit in my opinion.

If you reload a lot of .357 you should buy your self a Lyman M die and your problem will go away.

The cases are a mixture of batches, some new, some once-fired.
The press is a Lee Turret. Bought only to cope with .357 and small numbers. If it can resize smoothly - it does - then it should expand smoothly. The sizer is T/C from the same die set.
I'm tending towards the 'poor finish' on the plug being the starting point.
I've reloaded in the past (20 years ago) using RCBS dies and never experienced this problem. Lee were always thought of as the cheap alternative. I risked their press and dies but bought RCBS for the rest. The justification was small numbers. Bad choice methinks.

Hey ho, so it goes.

Thanks!

Try using some dry lube on the case necks. Imperial Dry media would be a good choice. When I used to load about 6000 .38spl a year for competition (1500, PP1 PP2 in the early 90's) I found that using dry media on the necks worked really well. i was using the same set up as you.The only dry media we had then was a Mica kit. I found that by grinding up the lead from 2B pencils and adding it to a 35mm film case full of no6 lead shot made an excellent dry media applicator. I still that method now.

The press shouldn't be your problem those early Lee turrets handle pistol rounds fine when all is working.

Did you buy the dies new are you sure the expander is the correct size.
I can not remember how the Lee set up works. I might have one laid about. I will have a look and remind my self.

You are seating the die correctly?. The shell holder should not be anywhere near touching the die, screw the die in until it just touches the shell holder, then back it out one full turn.

One other thing, it is def. the 357 set not the 38spl? The 38spl can load 357 but you would have to back out the Powder Thru Expander Die, and the Bullet Seating and Crimping Die about 2 turns to compensate for the longer 357 case.