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Reloading 357, is a crimp needed?

Hey all,

Working first time loading for a revolver, 357 mag. I have mixed hesd stamps, 158gr fmj and using H110. I found my issue, had to trim all the brass. My question is do I really need to put a crimp on the bullet? Does it matter? What will happen if I don't.
 
Been shooting the old 357 magnum since the 70's. Yes, for the reasons stated in the other posts, you need to crimp.

A taper crimp can be used on light target loads, such as when loading swaged lead bullet and wadcutters. However, in my experience, a roll crimp produces better results with full power magnum loads especially with the heavier jacketed bullets.

2400 is an excellent choice for magnum loads in the 357.
 
The H110 (WW296 same powder) is designed to work at maximum pressure, it has a very small minimum charge to maximum charge window, and a magnum primer should be used with this powder. It should have a very secure crimp to assure maximum pressure is attained. Hard cast lead needs a good roll crimp, jacketed bullets with a cannelure should also get a roll crimp or a neck down style crimp into the cannelure.
 
Ok. Ordered a factory crimp die tonight. I've load for 9mm and 45acp but never a 357. I've only got h110. I do have so mag primers, I will use them. Another issue I had was some of the loaded rounds would not chamber in the cylinder, found they where over length. I sorted 50 same brand same length and set the setting die to those. I think the issue was the other brass was the length, when I setted a bullet it pushed the brass down and expanded the brass at the web.
That's the only brass I have fired so far. I did a roll crimp on them. Also loading H110 at the min weight.
 
most 38-357 die sets have a roll crimp as a standard feature. factory crimp dies are rarely needed on revolver ammo, I use a taper crimp on swaged wadcutters in 38spl. and all 9mm, and 45acp ammo, h110 and 296 run best at top end loads never reduce these two powders below book mim weights
 

this works great with less than perfect brass lengths. Also works well on progressive setups.
 
I shot the .357 in IPSC competition for many years. Roll crimping
is essential. I do not advise a taper crimp for revolver use especially
under heavy loads. I custom cut a 168 gr round nose mold to make
speed loading easy, and developed a Blue Dot load for it.

And note that you want to crimp in a secondary operation so you
don't shave any lead, and in some cases, buckle the brass with some
copper jacketed bullets with no crimping groove.
 
Ok. Ordered a factory crimp die tonight. I've load for 9mm and 45acp but never a 357. I've only got h110. I do have so mag primers, I will use them. Another issue I had was some of the loaded rounds would not chamber in the cylinder, found they where over length. I sorted 50 same brand same length and set the setting die to those. I think the issue was the other brass was the length, when I setted a bullet it pushed the brass down and expanded the brass at the web.
That's the only brass I have fired so far. I did a roll crimp on them. Also loading H110 at the min weight.
You mentioned something I forgot to add. Case length is critical when using a roll crimp, cases should be trimmed to no more than plus (+) or minus (-) about .006" from your length. Too short the crimp may not be sufficient to properly hold the bullet under recoil. Too long the case will probably bulge/buckle at the case mouth when the crimp is applied. Something I did with all the revolver cartridges I load for was to get another factory seat/crimp die and remove the seating stem and use it as a dedicated crimp die only.
 
I don’t crimp unless the bullet has a crimp groove.
There is no way a die can seat and crimp and seat all at the same time, doing it properly.
If your cases are of mixed maker’s I suggest the taper crimp die.
Be aware that a taper crimp can size down a cast bullet in som instances.
 
I crimp most loads but the decision to crimp (and how hard) depends upon the bullet and the powder. Polymer coated bullets get a mild crimp so as not to impact/strip the coating. Slower powders/hotter loads usually need a firmer crimp with mostly jacketed bullets. As with many things in reloading, you will find a relative lack of a standard.

John
 
Have you read any reloading books on the subject, read this.
Good luck

When setting up my Lee crimp die I utilized one full turn per Lee instruction for a slight crimp.

View attachment 1324303
Interesting. When I read the instructions, I could have sworn it said a 1/2 turn was a light crimp?

1647460877420.png
 

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