M expansion die .38-40

[orpington]

Which one is recommended?

I regularly use M expansion dies in other calibers when loading cast bullets, but not with jacketed bullets.

Loaded .38-40 with jacketed bullets and crushed 2 out of 12 cases so obviously this doesn't work so well in this calibre for jacketed bullets.

Would 8.0 grains Unique for a revolver be too hot for a revolver behind a jacketed bullet, 180 grains? The Hornady reloading manual has this as a lower end load but something on the internet suggested 7.4 grains as a maximum load.

 

[orpington]

Finished up reloading and ended up with 46 suitable rounds. Crushed one other and a fourth round was rejected for other reasons. Would like to waste none, however.

 

[tightgroup tiger]

With 38-40 bottleneck case your better off seating and crimping in separate steps. As far as jacketed bullets goes, you must be using 40 S&W jacketed bullets, I don't think anyone is actively making .401 jacketed bullets.
Your M die is made for lead bullet diameter bullets which should be .402 if it is a 38-40 die and should accommodate the a .400 or .401 jacketed bullet.
38-40 cases have thin necks and are easier to damage than straight cases. Try seating and crimping in two different steps and use a neck resizing die in made for .401.
The thin necks need all the help they can get.

 

[orpington]

Yes .400 jacketed bullets. Using them up because I have some. Once gone, another 50 or so left, back to cast bullets only.