reloading question?

[mpjustin]

I am reloading some 357 mag for the first time and my seating and crimping dye keeps trimming a very fine bit of the case off (allmost looks like a heair around the bullet.) I can brush it off and then it looks fine.

Is this normal? and how can I get it to stop?
I have been using nickel plated cases.

thanks,
Justin

 

[Cerdan]

Crimping, especially roll crimping, can be hard on a case. Taper crimping doesn't bite the case so much.

Unless you're using a slow-burning powder like H110, you need only apply a slight crimp, just enough to prevent the bullets in the cylinder being pushed out by recoil.

 

[mpjustin]

Crimping, especially roll crimping, can be hard on a case. Taper crimping doesn't bite the case so much.

Unless you're using a slow-burning powder like H110, you need only apply a slight crimp, just enough to prevent the bullets in the cylinder being pushed out by recoil.

so do you think I am using to much crimp? When I compare my crimps to factory ammo crimps mine are much less and harder to notice. (almost half)
is it posible I could not me crimping enough?

 

[Cerdan]

It all depends on the burn rate of the powder you're using. Just because the crimp on the factory cartridges is greater than yours doesn't mean you should apply more. Judging from your other thread, I take it you're using relatively fast-burning powder in your loads, in which case I would recommend what I said above, using just enough crimp to hold the bullet tight. Excessive crimping only reduces accuracy and case life.

 

[mpjustin]

It all depends on the burn rate of the powder you're using. Just because the crimp on the factory cartridges is greater than yours doesn't mean you should apply more. Judging from your other thread, I take it you're using relatively fast-burning powder in your loads, in which case I would recommend what I said above, using just enough crimp to hold the bullet tight. Excessive crimping only reduces accuracy and case life.

thanks you for the help and advise. This is my fist time reloading a bullet where I have had to use crimping that why I am not sure. I will try to take some detailer pics when my wfe gets home with the camera.

I still don't know why I am getting the fine metal ring shaving of the case?
as long as I brush it off they should still be fine to shoot right?

 

[Cerdan]

The crimp feature on bullet seating dies (roll crimp) is really nasty on the brass, I get that fine metal ring as well when I use a heavy roll crimp. It's, quite literally, shaving a bit of life from your case. They're fine to shoot though.

I say again however, if you're using Titegroup, you really needn't apply so much crimp. In fact, I would recommend applying a light taper crimp. Get a Lee factory crimp die for that.

 

[proonur]

Is it even necessary to crimp at all? I don't reload 357, but I do load for 45 ACP and never bothered crimping with no problems at all.

 

[John Y Cannuck]

You need to crimp for certain slower burning powders, and for tube fed magazine rifles.
Other than that no, you don't really need to.
It gives you an option. See how your velocity consistency, and group size is affected by crimp. Some guns like it, some don't.
Never hard crimp a round that headspaces on the case mouth. A slight taper crimp if anything is all that's needed for them.

 

[Cerdan]

Is it even necessary to crimp at all? I don't reload 357, but I do load for 45 ACP and never bothered crimping with no problems at all.

You don't need to crimp cartridges for semi-autos, but you need to crimp heavy revolver loads because recoil acts as a bullet puller of sorts. I learned that the hard way. I was firing some of my first .357 handloads at an indoor range, fired the first shot and the cylinder binded. The bullets in the other six chambers were pulled from the cases just enough to peek past the edge of the cylinder, preventing it from revolving.

I had to call the RO over to help me. He used a copper rod to hammer the bullets back in the cases. Lucky they were hollow points!