The Firing Line Forums

Go Back   The Firing Line Forums > The Skunkworks > Handloading, Reloading, and Bullet Casting

Reply
 
Thread Tools
Old September 28, 2007, 11:25 PM   #1
actionflies
Member
 
Join Date: June 5, 2007
Location: Aloha, Oregon
Posts: 70
357 Magnum Crimp Question

How much should I crimp my 158gr. LSWC with my Lee FCD?
actionflies is offline  
Old September 29, 2007, 01:51 PM   #2
Daniel BOON
Senior Member
 
Join Date: June 5, 2005
Location: Henderson NV
Posts: 360
well.....

I crimp mine as tight as I can w/o indenting the bullet or lead;
Daniel BOON is offline  
Old September 29, 2007, 01:59 PM   #3
Linear Thinker
Senior Member
 
Join Date: February 10, 2007
Location: Blue State, NE US
Posts: 202
Since you are shooting lead, probably at medium velocity, heavy crimp is not necessary.
When you approach the max, heavy crimp is vital in magnum cartridges.
Lee FCD is easily adjustable, and in pistol cartridges the amount of taper crimp is easily measurable with a mike or a caliper. For revolvers, the roll-like crimp the FCD produces is not easily measurable.
LT
Linear Thinker is offline  
Old September 30, 2007, 06:43 AM   #4
WESHOOT2
Senior Member
 
Join Date: February 20, 1999
Location: home on the range; Vermont (Caspian country)
Posts: 14,242
what I do

I let the gun tell me.

I, using the superior Redding Profile Crimp dies (I use the LEE FCD for auto-loader cartridges), make test loads with varying crimp (it helps to have a range one step out my shop door).

Let accuracy guide your crimp.
__________________
.
"all my ammo is mostly retired factory ammo"
WESHOOT2 is offline  
Old September 30, 2007, 04:27 PM   #5
amamnn
Senior Member
 
Join Date: May 13, 2006
Location: WA, the left armpit of the USA
Posts: 1,323
At the risk of appearing to be one of the Rush Limburger intelligencia I must ditto WESHOOT's every point.
__________________
"If the enemy is in range, so are you." - Infantry Journal
amamnn is offline  
Old August 29, 2008, 04:44 AM   #6
sandro.1971
Member
 
Join Date: March 11, 2008
Location: Italy
Posts: 47
WSHOOT2, I also have Redding Profile Crimp dies for .357 magnum and .44 magnum cartridges.

Could you try to explain me what the right amount of crimp could be.

Let's say you put a resized case (but not expanded) into the shellolder and run it to the top of the press stroke. Then you screw the profile crimp die into the press until you feel it touch the case. In this position you get no crimp.

How many turns you apply to your die at this point ?

Also do you apply any lube before crimping ?
sandro.1971 is offline  
Old August 30, 2008, 10:20 AM   #7
WESHOOT2
Senior Member
 
Join Date: February 20, 1999
Location: home on the range; Vermont (Caspian country)
Posts: 14,242
I actually test

I let the die touch, twist it a bit, and load.
Then I twist it a bit more, and load.
And so on.....

Between each twist I shoot them to observe accuracy. I monkey around quite a bit; I have more than one die in each chambering.

'Medium' is a good place to start.



I lube nothing.
__________________
.
"all my ammo is mostly retired factory ammo"
WESHOOT2 is offline  
Old August 30, 2008, 01:26 PM   #8
sandro.1971
Member
 
Join Date: March 11, 2008
Location: Italy
Posts: 47
I'm trying to understand where the Medium is.

I did a search and read some of your posts. If I get it right you suggest to give a crimp that would reduce case diameter, measured just below the mouth, after bullet seating of 0.002 inch.

Could you post some pics of the rounds after the crimp ?

Last edited by sandro.1971; August 30, 2008 at 03:00 PM.
sandro.1971 is offline  
Old August 30, 2008, 04:14 PM   #9
Sevens
Senior Member
 
Join Date: July 28, 2007
Location: Central Ohio
Posts: 8,775
In .357 Mag, there are two things we are trying to accomplish with a crimp.

1) Keeping bullets from "jumping" forward under recoil
2) Holding the bullet in place to get a complete powder burn before it heads down range.

If you are using heavy magnum rounds with tremendous blast and recoil, it's time to put a firm roll crimp on those rounds so you get the performance out of your powder and so you don't lock up up the revolver with jumping bullets.

If you aren't using heavy loads, start with minimal crimp and see if you need more.
__________________
Attention Brass rats and other reloaders: I really need .327 Federal Magnum brass, no lot size too small. Tell me what caliber you need and I'll see what I have to swap. PM me and we'll discuss.
Sevens is offline  
Old August 30, 2008, 04:29 PM   #10
zxcvbob
Senior Member
 
Join Date: December 20, 2007
Location: S.E. Minnesota
Posts: 4,185
I just use the regular seating die to crimp. I put a resized, non-expanded case in the shellholder, tighten down the die until it touches, then go just a *little* more. (very little more). The mouth of the case (no bullet) is just slightly rolled in. Since the cast bullet is going to swell the case when it's seated, this ends up being a medium crimp and it doesn't overwork the brass. (I'm shooting maximum loads using Blue Dot, Herco, and AA#7 with 158 grain SWC's and RNFP's)
__________________
"The only way to stop a bad guy with a gun is with a good guy with a gun"
zxcvbob is online now  
Old August 30, 2008, 04:32 PM   #11
wncchester
Senior Member
 
Join Date: December 1, 2002
Posts: 2,832
It ain't critical.
wncchester is offline  
Old September 1, 2008, 09:08 AM   #12
WESHOOT2
Senior Member
 
Join Date: February 20, 1999
Location: home on the range; Vermont (Caspian country)
Posts: 14,242
what is "critical"?

I am unable to post pictures. Inspect Remington, Winchester, or Federal factory cartridges to observe crimp.

Crimp, IME, is extremely critical if accuracy matters.
I am (all too) aware that many 'reloaders' are only 'in it' for the cheap factor, and are more than satisfied if their 'ammo' goes bang safely.
But actual testing, as I described above, will teach open minds exactly how critical crimp can be.
I mean, I didn't invent this subject; someone taught me to "vary and test".....


I rest my case (oh, killin' myself still....).
__________________
.
"all my ammo is mostly retired factory ammo"
WESHOOT2 is offline  
Reply

Thread Tools

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT -5. The time now is 05:25 PM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2014, vBulletin Solutions, Inc.
This site and contents, including all posts, Copyright © 1998-2014 S.W.A.T. Magazine
Copyright Complaints: Please direct DMCA Takedown Notices to the registered agent: thefiringline.com
Contact Us
Page generated in 0.08731 seconds with 9 queries