357 mag crimp?

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Lead hammer

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Ok so I am working up test loads. I am using 2400 with Starline brass, small pistol primers.(non-mag) I am using Campro 158's. For my 9mm I taper crimp and after pulling some bullets for it, i have no deformation of the bullet and they work well. But for 357mag full house loads, google sometimes tells me to dent the bullet with the roll crimp (Lee), and some say just a small indentation. What are you guys doing?? I have 2 loaded with the 1/2 turn that Lee recommends for a light crimp, and the plating on the bullet is fine but has a .003" ring in it. Right now I prepped 200 brass but am stalled until I get this sorted.
Thanks
 
for jacketed rounds and lead rounds with a crimp grove, i put a heavy crimp on them. with berry's 158gr plated i put a noticeable crimp, but not enough to cut into the plating.
 
As above. It would be great if the berry bullets had a more substantial groove. Not in 357 but in a larger caliber I have had them work themselves out as the revolver was cycling. Never enough to lock things up or cause problems but 1/8" or so of travel.
 
I've never really checked, but I don't think I've had them come out from recoil, my 500mag on the other hand has, lots of times.
 
As soon as my dang iPhone is done updating, I will post a photo of the pulled Campro 158.
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Did testing using H110 max load with light to heavy crimp on Berry 158gn bullet. After firing the fifth round all the light/med crimp jumped. Only the heavy crimp didn't move. Used hammer puller, those bullet had a noticeable crimp, was surprised it didn't break through the copper plating.

No longer do max load with plated, only jacketed like XTP. Full load exceeds Berry max of 1250fps (Hodgdon H110 at 16.7 is 1591fps)
 
So what is a heavy crimp then? All I am going by is what the Lee instructions say. I may need to just shoot them but my range is blown in with snow still till it melts. I am using Campro and they are plated but claim that full power loads are fine since they have a thick plating.
 
A taper crimp should be no more than .002-.003 smaller than the normal outside case diameter around the bullet. The taper crimp should be called the miniscule case mouth streamlining crimp. Remember bullet tension is controlled by the diameter of the case and the cartridge headspaces on the case mouth.

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Below my miniscule streamlining almost a crimp on my .40 Glock and plated Rainier bullets.(50 rounds)

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I also taper crimp my light practice .357 and .44 Magnum using plated bullets. Please note the powder is 100% burnt at 2.4 inches and does NOT require a heavy crimp.

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Last edited:
Spawn-Inc said:
In you second picture, that's a moderate to heavy crimp for me with plated, Looks plenty fine.
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Ok thanks, I measured the bullet above and below the crimp line and the bullet diameter is unchanged. I think I will give it a go. Both photos are of the same bullit, dang iphone 4.
 
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