What is causing this?

[duckslayer56]

Other than the pic loading upside down, what is going on with these loads?

I was loading up some 357 Magnum loads tonight, and this is the second time I have run into this problem. These 4 loads were the only ones this happened with out of 50. I run into this problem on the crimping stage. This happened with the previous batch I loaded as well with about 3 loads out of 50. I am using Hornady dies, and these seem to be the only dies I have this problem with.

Is something catching on the expanded case mouth and crushing the case?

[BrownBear]

If you miked those cases, odds are they're longer than all the others in the lot. When you go to crimp, the die is pushing the case back in the process.

[marshall]

If you miked those cases, odds are they're longer than all the others in the lot. When you go to crimp, the die is pushing the case back in the process.

I agree. A few cases are to long or your die is adjusted to far down.

[pinehavensredrocket]

possibly the case is buckling before the bullet is crimped...bell the case mouth a bit more to alleviate that problem. good luck.

[BrownBear]

possibly the case is buckling before the bullet is crimped...bell the case mouth a bit more to alleviate that problem. good luck.

That's another very good possibility. Might even chamfer them lightly beforehand.

[tvfinak]

The Lee factory crimp die should iron these creases out so at least you can shoot them and perhaps reclaim the cases.

My guess is the cases are too long or you are aren't lined up with the crimping groove in the bullets.

Trying to seat and crimp in one operation with jacketed bullets can also be problematic - jacked bullets are less forgiving that lead ones. Try seating in one step and then crimping in another. After seating and before crimping check for alignment of the bullets in the cases -the crimping grooves are a good reference to compare and you can probably pick up some longer cases or other issues.

[duckslayer56]

This helps out a lot, I didn't mic all the cases. They are all the same batch of brass. I seperate all my brass into bags of 50 and don't mix them with any other 50 cases. I then mic 1 out of every five when reloading and I generally find them all about the same. I guess I just need to spend the time and mic all of them before I put them in the press.

Thanks for the help.

[BrownBear]

This helps out a lot, I didn't mic all the cases. They are all the same batch of brass. I seperate all my brass into bags of 50 and don't mix them with any other 50 cases. I then mic 1 out of every five when reloading and I generally find them all about the same. I guess I just need to spend the time and mic all of them before I put them in the press.

Thanks for the help.

Sounds like you're pretty squared away, so I'll change my "vote" and go with pinehavensrocket. I'm familiar with it in that circumstance too because I hate to bell the mouths any more than I have to, in order to extend case life a bit. I bet if you turn the belling plug down about half a turn, the symptoms will go away.