38-55 Cases Deforming

[steelersfan]

I finally got all my stuff together to reload (newbie) my 38-55. I selected 20 random cases from my bag of 50 Winchester cases and began the process.

When I got to the expanding die step, I ended up ruining a good 3 or 4 cartriges by rippling the mouth edge. I couldn't pinpont what I did different for these cases.

I ruined a deformed a couple more case mouths when I seated the bullet. The edge of the case mouth deformed.

It may have been operator error I dunno.

Could it be that the case mouths weren't perfectly round that caused the problem? Also why are these cases so darn fragile and thin?

What can I do to avoid this in the future.

[Nobade]

Are you full length sizing them first? If not you should, since the factory new cases are never round. Otherwise, make sure your belling die is set properly (not too much bell, just enough to get the bullet started) and be careful. Take your time and make sure everything is lined up when you pull the handle. And yes, those cases are thin and fragile. Just wait until you start doing 32-20!

[3006va]

After sizing you should also check for proper uniform length. HTH Aaron