how do you fire form 30-30 brass to make .357 Herrett brass?

[Greenhunter]

Can anyone please tell me exactly how you go about forming .357 Herrett brass from 30-30 cases? I have experience in reloading but not in reforming brass into another case size/dimension. 

[Graybeard]

The first step I take is to run the .30-30 brass into the .357 Herrett die. I then trim them to length and deburr inside and outside. Then ya load and fireform. It's really pretty straight forward. Trimming is the headache of it. Some use a file trim die for it but I've just used my trimmer but I also picked up a Forster for use with drill press. You clamp the brass down in it and use the drill press to trim. It's faster and easier but unless the stop on your drill press is more accurate than mine you'll still need to do the final trim on a regular trimmer. I got it for making .30 Herrett cases as they must be trimmed a lot more.

[cwlongshot]

Bill's description is how I have done it too.

 One thing I do different is cut the long necks close with my dremel tool and a cut off wheel. Then deburr the inside, then trim on the power trimmer. Lastly a final dedur of the neck and flash hole.
 Its not required, but I got my best cases loading a long bullet to touch the rifling with a lite charge of powder. Just for the first loads. Then regardless of your chamber, your brass is perfect. I found it necessary to do this every couple loadings. But that should not be necessary. I now feel that my loads where a bit hot. Not in pressures, but by design. I think the frame was moving/stretching and causing the problematic ignition I was experiencing. My newly fire formed cases worked perfectly for 2-3 firings then miss fires would begin again.

 The shoulder isn't fully formed, but there is plenty there for first firing. After first firing you will have the actual 357 Herrett case. BECAREFUL reloading these. There is not much shoulder and moving it when resizing is a big problem for this caliber. Its the biggest reason I gave up on it. When setting up your dies, AFTER initial forming. Be sure you smoke the necks of the brass and set the die so as not to move the shoulders or miss fires will develop.

If you want some great reads about this caliber. Google Steve Herrett and Bob Milek the designers of this fine cartridge.

 Good luck,
 CW

[Grumulkin]

Get a trim die.  Run the 30/30 brass through the 357 Herrett die and use a hacksaw to do most of the trimming and then clean it up with a file.  Load and shoot.

The rim on a 357 Herrett case is for headspaceing.  It's true that headspacing on the shoulder will improve case life but I've not had any problem resizing and shooting without being compulsive in this regard.

If you want to take the easy and more expensive way out, you can get new 357 Herrett brass from Quality Cartridge.

[Lone Star]

The rim on a 357 Herrett case is for headspaceing.  It's true that headspacing on the shoulder will improve case life but I've not had any problem resizing and shooting without being compulsive in this regard.

Perhaps you have had no problems, but the developer of the cartridge certainly disagreed.  So many Herrett loaders had headspacing problems that Milek wrote at least two articles carefully outlining why not to headspace on the rim and how to set up for headspacing on the shoulder.  Out of over 500 cases made, the only Herrett cases that ever gave me problems were from a batch I sized to headspace off the rim (by accident, I bought a new press but didn't chech the die settings).

If your chamber and sizing die match headspace dimensions then you won't have problems, but T/C chambers are notorious for differing dimensions.  My two .30 Herrett barrels could not use the same ammunition due to a rather large headspace difference, so I had to use different brands of brass for each.  No problem.


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[Grumulkin]

Yea I know, a lot of people have had problems with the Herrett cartridges but I haven't.  I guess I'm lucky.

Let's face it, the Herrett's are work intensive and really probably not worth it with the other cartridge choices out there today.  Why do I still have mine?

[Graybeard]

Back when I still had TCs before I gave them up and moved on to other things I liked my Herrett's and never had any problems with either the .30 or .357. Case forming is a pain but once it's done they last almost forever and I never had a misfire with one.