Help on .357 Herrett needed!

[jschance]

I'm having problems forming the brass for my new .357 Herrett.  Here's what I've done so far and the problem I'm encountering.
 
I purchased the Hornady dies and 100 pieces of Remington 30-30 brass.  I resized a handful of the 30-30 cases without trimming them to length first, and realized that the end of the case was hitting the top of the die and decided to trim them first.  I made a trim jig and proceeded to cut the cases off at about 1.85, with the intent to trim them down to the required 1.750 after resizing to .357 Herrett.  I used a fine toothed hacksaw to cut the cases off, then ran them through my trimmer to clean up the cut.  My trimmer was leaving a fair sized burr on the outside of the case neck, so I spun the cases in a cordless drill and used a fine file to knock the burr off.  I then chamfered the inside of the case using a Lee chamfer tool.
 
The problem I'm running into is in the first 10 cases I split the necks on 7 out of the 10.   The only thing I can think of is I work hardened the case necks in the trimming process and I need to anneal them.  I'll try that tonight on a few cases and see if it helps.
 
Any other thoughts from you folks that have been reloading the Herrett rounds?

[skb2706]

I haven't worked specifically with the Herret but I have worked with several 30-30 based case forming operations. It tends to work harden very easy but is easy to anneal as well. There are several ways to do that I just use my old gas stove and a bowl of water turn the case neck/shoulder area in the flame for a given amount of time and toss them in the water.

[Old Syko]

Just another reason I don't like using Remington brass.  I've had the same results as you are having, split necks due to brittle brass.  I'm yet to have the same problem with Win. brass so that's what I use.

For the 357 Herrett I quit using 30-30 brass and now use 375 Winchester brass instead.  I've found it easier to size initially and it lasts 50% longer.  I've done this on the advice of someone I met here on GBO and found it to be good advice.

BTW  Also sounds like you could use a good chamfer tool for both i.d. and o.d. like the one RCBS offers.

[jschance]

I'm not so much inclined to blame the brass as delivered, because I was able to resize 8 or 10 cases with no splitting before trimming them.  

I'd resize them all and then trim them, except for the problem of the brass hitting the top of the die when full length.  You can tell this because there's a high degree of resistance to pulling the resizer plug out of the brass on the downstroke of the full lengh 30-30 brass.

I thought about using the .375 brass, but when I ordered things, there wasn't any available from Midway, so I went with the 30-30.

[Moe]

Who has .375 Win brass for sale??

[drichi]

I believe graf and son has 375 brass. I use a form and trim die to make herrett cases and find it to not be much work with a fine tooth hack saw, and then chamfer and run into a herrett die. the only thing I use is 375 win. brass.  drichi

[MS Hitman]

My processes for making .357 Herrett brass.

Using .30-30 brass:

1. Trim case to 1.765"
2. Run case through Herrett sizing die
3. Fireform case
4. Square up case mouth and trim to 1.75"

Using .375 Win brass:

1. Run case through Herrett sizing die
2. Trim to 1.760"-1.765"
3. Fireform case
4. Trim to 1.75"

Certainly not the only way to skin this cat, but works well for me.

Hope this helps.

[jschance]

For everyone who was waiting with baited breath, it was definitly a case of work hardening of the case mouth.

I annealed 5 of the cases after work last night, and every one of them went through the resizing step flawlessly, so I went ahead and annealed the rest of this batch.  I was able to resize all of them without another loss.  Now I know.


I'm still learning on making the Herrett brass, so all these good recommendations, I'm writing down.  

[Old Syko]

I think you'll find it's not so much a problem with work hardening as it is with case hardening due to the build up of excess heat during your trimming procedure.  This is what also caused the flare on the end of your cased rather than a clean square cut.  Many things cause this including too fast of trimmer speed, dull cutting head, shock cooling after the cut, etc.  I always have full length sized all my brass once my die is set, which means I have to trim to length 2 or 3 cases first in order to get proper head spacing, then set my die.  I then size that run of brass, then trim to length.  Be sure to lube the inside of the necks also for the expander ball or you'll be quite unhappy when the case head pulls off on the downstroke leaving the case stuck inside the die.

[jschance]

Update on the Herrett experiment.
 
Last week I determined annealing the brass was required to eliminate splitting the necks when sizing up to .357, and this worked quite well.  I started trimming them down to the final length (prior to fireforming) and decided that I didn't like turning the crank on my Lyman trimmer, so I called up Midway and ordered the power adapter.
 
All I can say is if you have been debating getting one of these, DON'T!  Crack open the pocketbook and order one today.  I've decided that that was the best $16.49 I've ever spent on reloading equipment.  I was able to trim down about 45 cases in less than 15 minutes.  It took less than 5 minutes to switch from the manual crank to the power adaptor.  I then hooked up a 9.6v cordless drill and went to town.
 
I've now got 50 pcs of sized, trimmed, and chamfered brass waiting to be loaded up and fireformed.  With a little bit of luck, I'll be at the range Saturday, testing out my Herrett.