Undersize dies

[jculloden]

What the purpose of the Lee 38spl undersize die? Thanks

[Ivan the Butcher]

Any brand of Undersized / minimum sized dies take the cartridge way under the normal size of the marketed cartridge. Hornady did the same in the early 80's, and I bought a set of 38/357. Ito took the body of the cartridge down to a so called minimum diameter! Then when you seated a bullet, especially a jacketed bullet the center of the cartridge was "WASP" shaped. On soft lead bullets it constricted the bullet diameter. If you used hollow base bullets, the hollow would expand to take the refiling. These "Skinny" shells would feed in tight chambered firearms.

It works the brass several times more than normal each time they are use for reloading!

Ivan

[DWalt]

I was unaware of such dies in use for handgun calibers, but have seen the so-called "small base" sizing dies available in specific rifle calibers. They are intended for loading cartridges used in some semiauto rifles and resize cases to SAAMI minimum dimensions to ensure there are no chambering problems as the result of a tight fit in the rifle chamber.What would be the advantage for using minimum sizing dies for use with revolver cartridges?

As a side note, I own several semiauto rifles in .308, .270, and .243 and have encountered no chambering problems when using reloads with cases resized in normal dies.

[Skeet 028]

Only undersize dies I could have ever used...maybe...was 308 when someone gave me a bunch of brass used in a MG. Some you could not get to size correctly due to springback I guess

[robertrwalsh]

I use an undersize die regularly on initial sizing for once-fired purchased .40 caliber. I have found it to be necessary. Other than that it is, as far as I can tell, unnecessary work and unnecessarily hard on the brass, shortening it's life.

[Forrest r]

I thought the lee 38spl/357 undersize die was used to undersize the case mouth only. This allowed the reloader to use smaller bullets.

[max503]

Originally Posted by jculloden

What the purpose of the Lee 38spl undersize die? Thanks

Maybe its' purpose is to let you reload 38's with 9mm boolits. I have an H&R Handi Rifle with a tight bore. It works best with .355" jacketed boolits.

[rosewood]

Originally Posted by robertrwalsh

I use an undersize die regularly on initial sizing for once-fired purchased .40 caliber. I have found it to be necessary. Other than that it is, as far as I can tell, unnecessary work and unnecessarily hard on the brass, shortening it's life.

I originally bought the small base die then discovered the bulge buster kit.

A lee bulge buster kit with their factory crimp die with guts removed does a better job than the "small base" die. Evens the brass all the way from top to the over the rim. Same setup works with 10mm also and 357sig, 9x25 dillon to straighten the fattest part of the cases.

Rosewood

[rosewood]

Undersized dies are just ones that were made with a wore out reamer and out of spec....the manufacturers figured out they could market them and still make money...

I honestly have never had the need for a small base die. At one point I thought I did, then I found a better mouse trap.

I think the real problem is, most dies don't go down far enough to straighten out the case to where it needs to be, a smaller base die will push the part of the case in the die down to below spec, and the adjacent brass of the case outside the die will also be pulled down with it so it fits in the chamber. It really doesn't fix the problem. Probably ultimately works the brass more too.

Rosewood

[Krogen]

I don't know about the 38 Special, per se. I can talk about the 9mm Luger, though. Maybe it's a similar situation when 38 Specials are fired in a Model 52. My Springfield Garrison in 9mm has a distinctly tight chamber. Some reloads will jam with the slide slightly out of battery. It can be a real pain with the 9mm's tapered case. 38 Special in a Model 52 may not be so troublesome. FWIW, the problem is specific to the Garrison; none of my other 9mm's have this problem.

Midway has this to say about the 9mm Luger and undersized dies:

"Lee U Carbide Undersized Sizing Dies are great for reloaders looking for ultimate feeding reliability in their handgun. These dies undersize brass between .002" and .003" smaller than other Lee Carbide Sizing dies. Ammunition with undersized brass cases will chamber each and every time it is loaded out of a magazine giving reliable chambering each time a round is stripped out of the magazine or loaded into a cylinder. Competition shooters rely on having ammunition that will feed and chamber each round of ammunition as it is stripped out of the magazine."

Midway: 9mm Undersized Dies

[DWalt]

I have had some previous experiences with reloading GI .38 Special cases that resulted in cartridges which were difficult to insert in revolver chambers. That may have been because the brass sidewalls were thicker than civilian brass. Maybe the undersized sizing dies would have helped. In any event, I ceased reloading GI .38 Special cases. I never had very many of them to begin with.