Folks ,
I haven't loaded any .357 in years . I do recall I use to set up for .38 Spec. and when I went to .357 I just backed out the die , slipped a spacer on and screwed it back and started on the .357

Now I'm loading on a Dillon 550C , there's not enough room to add washer type spacers under the dies .
Has anyone got a square plate or spacers for this situation . It would also apply going from .44Special to .44 Magnum but the spacers would be thicker .
Thank you in advance for your time and help.

Semper Fi,
Soup

Just curious, what brand of dies were you using? This is nothing that I am familiar with. I'm not claiming to be much familiar with anything other than the brand I usually load with. I load a fair amount of .38 Spl & .357 Mag with the same dies and also .44 Spl & .44 Mag with the same dies, using a single stage press. I have to readjust my dies when I change from one to the other. This might be an interesting concept.

Redding Dies
.38 Special = 1.15
.357 magnum =1.29
.14 difference

Once the Dillon is set up I usually don't fiddle with anything. I do most of my 38/357 and 44 on a Rockchucker and the only lock ring I set is on the flaring die, and I use the same spacer on the 38/357 as for 44 mag/special flaring - don't even remember where it came from. I think RCBS(?) used to offer spacers in different thicknesses but haven't seen any in ages.

I switch back and forth often between .357 and .38 special. I am not using a Dillon though, just a single stage RCBS. I use the spacer ring on the expander and seater dies, but not on the resize/decap die. That one has to be adjusted each time.

midway sells a die spacer for about $7

Thanks for the info. I finally found them, but I cannot use them. I have a Lee press that uses the quick change bushings and spacers cannot be used on these as my dies stay attached to the bushings. I just pop them in and out of the press when I need to change to a different die.

Redding: (Different thicknesses for .38/.357 and .44 Spl/Mag):

https://www.redding-reloading.com/online-catalog/98-die-spacer-kit

I know Redding makes a spacer kit , but you can't use washers on a Dillon 550 head . There's not enough room

Stiff rubber 7/8 id .14 thick orings would work. The o ring sits under the lock nut and doesn’t protrude past it. Or just readjust the dies each time as was mentioned

Readjust dies. Make a mark and carefully count the number of turns. Once you figure it out you can go back and forth pretty quickly. Or just buy a second die set so you have one adjusted for .38 and one for .357.

I've had my RCBS dies for .38spl/.357 for a looong time. I just use the provided spacer on the .357 on everything but sizer. Spacer is, I believe 0.125".

Well y’all learned me something today. Last week I ran a new Starline .357 case into a flaring die set for .38 Special. New Starline brass is a terrible thing to waste. I’ll have to acquire a few of these magic washers.

RCBS will probably send you a free one. Call 'em