357 mag Crimp

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Keeebs

Keeebs

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Hello, I'm new to reloading. I feel I have the basics down, but I'm not sure I'm crimping correctly. I'm using LEE 38/357 4 die set which has a crimper. I've followed the instructions and I'm set to "light crimp". I can't see the crimp, feel the crimp or measure the crimp. Is there a trick to test if you have enough crimp? I'm not sure if I even have a crimp at all, I don't feel any resistance when the bullet goes into the crimp die.

357 mag revolver.
Hornady 158gr XTP
Powder: 2400
13.7gr, 14.0gr, 14.3gr (I'm working up a load)

Picture on the Left Federal factory load, Right My Load.
 

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2 Things I can see from your picture:
First, you need to seat the bullet a little deeper so that when you crimp you are crimping into the middle, or deepest part of the cannelure.
Second, you're right, there doesn't appear to be any crimp on your round. Re-read the instructions on the Lee Die and set for a heavy crimp.
I use a heavy crimp on all .357 and .44 magnum revolver rounds. Not enough crimp and your bullets will "run-out" from the heavy recoil and jam your revolver.
I'll give credit where due for my response. I learned this from asking questions on here just like you. Thanks THR!
 
Definitely seat that bullet a wee bit deeper. It looks like you have taken the flare out, but just not rolled it in enough... adjust the die down.
 
Try turning the whole seating die down a quarter turn and try running your load into the seating die again. It should add some crimp and seat deeper at the same time.

I don't normally use the 4th die.
 
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.357mag.jpg
That's what it should look like, Take an empty case. put it in the shell holder and raise the ram all the way up. Screw the bullet seater of the die up in the air away from the bullet and screw the die body down until you feel the crimp part of the die hit the mouth of the case.
That will be where the crimp process will start. Now take one of your loaded rounds and put it in the shell holder and raise the ram up the whole way again then screw the bullet seating stem down until you feel the top of the bullet.
Then lock it down. Then screw the die down a half a turn and see if the crimp doesn't start to form. Screw the die down until the middle of the cannular is showing and at the same time the roll crimp should be getting stronger.
Lee Q Loader is right, your bullet should be seated a little deeper.

I haven't used Lee dies since the 1990s so I am assuming the seating die is their standard seating/crimping die.
 
The set I have bullet seating and crimping are 2 dies.

The Lee crimping die is pretty straight forward with instructions, die touches shell holder, insert loaded round, turn adjustment until you feel it touch the bullet, remove round then 1/2 turn for light 1 turn for heavy. Sounds like I just need to go a bit heavy.

My COL is 1.590 which is max so I can go further. I guess once I actually crimp, the crimp should land center?
 

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Difficult to discern from the photos (post 1) but the crimp looks to be light to very light. For starters, seat a tad deeper so the top of the cannelure is just barely visible. The left round is close...may be good but could go a tad deeper. The right appears long. I separate seating from crimping, so I'm using four dies. Many combine seat/crimp in one step but from a physics standpoint...hmmm.

It's common to adjust crimp relative to the charge for a few reasons. For a light load, such as low/mid 38 Spc, a taper crimp is ample. Heavy loads require a heavy roll crimp as it prevents bullet jump due to recoil, potentially locking your cyl. On heavy loads it also ensures 1) better/complete ignition of the powder and 2) proper pressure before launching.

PS - Photo in Post 6...seat deeper yet, for a just barely visible cannelure.
 
The lee crimp die is the best there is (IMO) just keep turning the center in until you can't catch the edge of the case mouth with a fingernail . that's enough for 357. Either way , even if over adjusted it won't buckle th case.im guilty of over crimping , but I don't care, brass is cheap and it aids in consistent ignition. Can't say you should seat bullet deeper for sure, depends on if your cases vary in length, if all the rounds have the same look (completely exposed cannelure) seat deeper. Sometimes if you have a pile of random range brass some will be short and look like that, if they all look like that pit them in at least to the center of that serrated band.
 
I moved a few rounds down a bit.

Left to Right. Factory, Light Crimp, Heavy Crimp, Then another 1/2 turn for heavier. I can't see the difference. I'm going to call Lee tomorrow, maybe there's something wrong with my die or I'm over looking the obvious. But I don't think my crimper is doing anything.
 

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I use Lee carbide 4-die sets too.

Put the round back into the shell holder and seat that bullet a bit more. Don't worry about the OAL (but measure and record it if you like.)

Then run it up into the crimp die. Bring it down and look at it. If it needs more, adjust the die a little and try again. Keep doing that until it looks like the photo tightgroup tiger posted.
 
Use your seater die to crimp.

Back the seating plug all the way out. Raise a loaded round all the way up. Tighten in the die until you feel it contact the case mouth. Now lower the ram and turn the die in a quarter turn. Raise the cartridge back into the die. Take cartridge out and inspect the crimp. Keep doing this until the crimp looks good.

Once the crimp looks good, raise the cartridge back into the die and screw the seat plug down until it firmly contacts the bullet.

You are now set to seat and crimp in one operation.
 
Lee Q. Loader said:
2 Things I can see from your picture:
First, you need to seat the bullet a little deeper so that when you crimp you are crimping into the middle, or deepest part of the cannelure.
Second, you're right, there doesn't appear to be any crimp on your round.
Click to expand...
Agreed.

A crimp thread

A couple of pics from that thread.

.357 Mag.
index.php

index.php


.44 mag, but it shows what @Lee Q. Loader posted.
index.php
 
tightgroup tiger said:
You don't have a taper crimp die do you?
Click to expand...
I agree, it sure looks like he has a taper crimp die instead of a roll crimp die, which is what he really needs for Magnum revolver cartridges. I would also suggest seating first in a separate step and then crimping. Trying to apply a uniform roll crimp while seating the bullet doesn't work well. Although it takes longer adding a separate crimping only step, it is worth it.
 
I moved the bullet down and the crimp roll is landing center of the cannelure. I stood the bullets on the nose to gauge center, I'm thinking this is about right, please advise.

I"m not going to say lee products are the best, but there customer service is outstanding and very helpful to a new reloader.

2 things I learned today, the crimp die in the 38/357 4 carbide die set is a "Modified something something something" They said it's a tamper die that can also roll crimp. If that makes sense to someone please explain for the next newbie that stumbles on this page.

Based on the instructions it says adjust the knob down until you feel the bullet. Well that just wasn't working, so turns out my understanding of "Feel the bullet" is different from others. And turns out "feel the bullet" is to adjust down until you hit a hard stop, I was feeling resistance and assumed that was the right depth. Please see the 2nd picture. This is the crimping part of the die (It's currently upside down to show the grove) the bullet must travel through before the case mouth hits that inner lip. As you can image there is resistance as the round moves through.
20200326_172632.jpg
20200325_190200.jpg
 
How I do my Lee factory crimp dies is to put a case with powder and a bullet set in the case mouth in the case holder. Then back the bullet seating stem way out. Then close the press and screw the die in until I can feel a little resistance from the case mouth, just touching. Then I screw the seating stem in and dial my OAL in slowly, a bit at a time. Once that's set, I back the seating stem out a few turns, and maybe 1/4 turn at a time screw the whole die in to set my crimp where I want it. Then, with the finished round still in the press, screw the seating stem back so it's touching the nose again. It goes pretty quick once you've done it a few times.
 
OP, you want to crimp with a separate die/ separate step from seating? That's my choice although lots of people seat and crimp with one step/ one pull of the handle when hand loading.

I'll look up my COAL for both 38 and 357, and post it, tonight.
 
yes, seating and crimping are 2 separate dies. The latest rounds shown are 1.280.
 
Keeebs said:
I moved the bullet down and the crimp roll is landing center of the cannelure. I stood the bullets on the nose to gauge center, I'm thinking this is about right, please advise.

I"m not going to say lee products are the best, but there customer service is outstanding and very helpful to a new reloader.

2 things I learned today, the crimp die in the 38/357 4 carbide die set is a "Modified something something something" They said it's a tamper die that can also roll crimp. If that makes sense to someone please explain for the next newbie that stumbles on this page.

Based on the instructions it says adjust the knob down until you feel the bullet. Well that just wasn't working, so turns out my understanding of "Feel the bullet" is different from others. And turns out "feel the bullet" is to adjust down until you hit a hard stop, I was feeling resistance and assumed that was the right depth. Please see the 2nd picture. This is the crimping part of the die (It's currently upside down to show the grove) the bullet must travel through before the case mouth hits that inner lip. As you can image there is resistance as the round moves through.
View attachment 902562
View attachment 902563
Click to expand...

Looks okay to me. I usually seat just a little farther in, about 2/3rds of the cannelure inside the case mouth. I'm not saying that's "correct", it's just how I do it.

Now do the rest and go shoot them. :)
 
"Modified something something something" They said it's a tamper die that can also roll crimp.
Click to expand...

Not tamper crimp, Taper crimp. Yes this is a taper crimp die that if lowered enough will also roll crimp. Its called a modified crimping die. That's why you were feeling resistance and not getting a roll crimp. You were feeling the taper crimp that comes first.
If you load plated bullets and are loading light to mid range loads, the taper crimp part is all you need to use.

Loading above mid range to full house loads you need to use the roll crimp part.

The crimp in the top picture looks good for heavy loads. I think your in business.
 
Please check all loads in a modern, published manual- these worked well in my setup:

RCBS Single Stage Press with RCBS #18215 Die Set. Note, All were used as pistol cartridges and all crimped w/ Lee FCD instead of using the RCBS taper crimp during seating.

The 38 Spl. bullets were ONLY 140 gr. Sierra #8325 JHC.

The 357 Mag. bullets were 140 gr. JHC, or 158 gr. SWC bullets. 357 Mag. powders included Unique, Power Pistol, and W231. Preferred was W231.

38 Spl. COAL 1.450"
357 Mag. COAL 1.590"
 
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Since I am OCD about crimps, I would seat the bullet a hair more, but it's looking very good.

Clean out that crimp ring after a session.

If you deburr/chamfer cases prior to it won't remove material as bad, and if you don't it won't do it as bad the next times you crimp the cases unless you trim again.

A "modified" roll crimp on a .32 Mag
Modified Roll Crimp on a 100 Gr XTP in .32 Mag Pic 1 @ 75%.JPG
 
Keeebs said:
Is there a trick to test if you have enough crimp?
Click to expand...
No trick, use your calipers - Your later pictures show a pretty good crimp in the cannelure, you can measure before and after crimp. You can also visually verify you’re rolling that case mouth into the bullet.
Since you indicated you’re new to this, keep in mind roll crimping like this requires all your cases to be at the same trim length. Even if you’re using “new” brass, you may want to check to make sure the case OAL is the same or within a couple of thousandths.
Keeebs said:
yes, seating and crimping are 2 separate dies. The latest rounds shown are 1.280.
Click to expand...
Good deal on the two separate operations - that’s what I do and find it an advantage to have more control over those two operations. However, I’m not sure what you’re saying about the 1.280? Maybe a typo and should be 1.580 hopefully?
Good luck and welcome to THR and the addiction!
 
I'm pretty new to reloading, but for crimping pistol cases, I've done a few sets of .38 Special which is similar - you should feel a firm resistance in the arm of the press when you do the crimp. It should not be hard nor should it be so light you don't notice for a roll crimp. Probably best described as a light to modest, but firm resistance on the crimp. That's been my experience - once you've zoomed in on pictures and sort of figured out the right crimp for your loads, you basically could do it by feel.
 
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