357 Magnum Woes

[Olon]

In all of the 357 mag I've loaded, I have never gotten the crimp figured out. No other cartridges have given me troubles with crimp.

For some reason, I'm getting such little neck tension that the bullets can be spun around after crimping... this is with new starline brass at exactly spec dimensions as well as brass stamped RP. The loads are accurate but it just bugs the ever living you know what out of me. Even if the case is completely unbelled, I can seat a lead or plated bullet without shaving and no matter how tight I crimp, the bullet usually can spin. Any idea what's going on here? Is it even something that matters? I'll shoot these from my Henry 200+ yards occasionally and frequently between 100 and 150.

I dont think I'm over crimping because with any less crimp, I can slide the bullet back and forth in the case with just my fingers.

It's confounding and I'm just not sure what the issue is. Any advice is greatly appreciated!

 

[AJC1]

My first guess is that your bullet is too small can you take a measurement and share

 

[243winxb]

Lee crimp die?
.

 

[Armored farmer]

^^^^this
Or you may be flaring too much.?

 

[mjsdwash]

maybe just a defect? Its pretty possible the die body is not square to the ram, and not allowing full crimp, or the body is just too long. Maybe the die is assembled wrong? My Lee dies will completely buckle the case with just the bullet seater turned in too much, as should any .38/357 die. Are these 357 specific? If there like a normal die, they should be able to heavily crimp the shorter .38 case, and you back out to do .357. Edit to add, this is a mechanical problem. .357 is the easiest caliber to reload, and I recomend it because its foolproof, assuming everything works. BTW, if you are using a Lee FCD, those things require some insane pressure to crimp, and you may just not be doing it enough. I do .223, and it makes the press creak. Normal pistol dies have an integrated crimp in the seater, and this works perfect for .357, if using the correct bullets.

 

[AJC1]

We have two different competing ideas here one is that you're using lead and your swaging down the lead by using the Lee Factory crimp die and I'm wondering if you're accidentally loading 9 mm jacketed bullets in a 357

 

[Mn Fats]

Lee crimp die?
.

I use a set of Lee's for LSWC. I've actually never needed to crimp 38/357. If you can twist it, I'm guessing your bullet is wrong.

 

[Mn Fats]

^^^^this
Or you may be flaring too much.?

Even so, it would either not fit in to the die, or fit in and neck back down.
Edit: With the right bullet.

 

[joneb]

I use rcbs dies which do a pretty job, but if I need some extra crimp I use this https://leeprecision.com/357-magnum-custom-collet-style-crimp-die.html This is a collet crimp die that does not resize the loaded round.

 

[AJC1]

I use rcbs dies which do a pretty job, but if I need some extra crimp I use this https://leeprecision.com/357-magnum-custom-collet-style-crimp-die.html This is a collet crimp die that does not post size.

I like the collet rifle crimp dies, I was unaware they had them in pistol. Nice

 

[film495]

just the tension on the bullet should prevent the bullet from spinning, even with no crimp. measure the diameter of the case where the middle area of where the bullet will be seated before and after crimping. sounds like it would be pretty much the same so - it should be like .002 difference I think. your expander die is probably expanding the case too much, if you are using the correct case and bullet combination. the crimp is an extra hold, but the tension of the bullet expanding the case when seated should grip it firmly.

 

[Obturation]

Picture of the bullets or mould you're using and your dies would help. I have no trouble crimping with Lee fcd, in fact I think I'm too good at using it . You get bullets pushed down into the case if they've been loaded in the tubular magazine?

 

[Mn Fats]

Picture of the bullets or mould you're using and your dies would help. I have no trouble crimping with Lee fcd, in fact I think I'm too good at using it . You get bullets pushed down into the case if they've been loaded in the tubular magazine?

OP must be loading tube. No benifets on crimping for a six shooter.

I'd also like to see pics of the die and brand of bullet.

 

[9mmepiphany]

I can slide the bullet back and forth in the case with just my fingers.

I've seen this when a friend came over to use my press/dies to reload some ammo. He had previously used his Lee dies to resized, deprimed and primed the cases.

He was occasionally getting bullets dropping into the case with almost know resistence. Without fail them turned out to be R-P cases. I resized them in my Redding Carbide Dual Ring Sizer and they worked fine.

I'm interested in which bullet you're using as well as the diameter of the slug. Also interested in knowing which die set you're using

 

[joneb]

I like the collet rifle crimp dies, I was unaware they had them in pistol

For 357 mag and 44 mag with heavy loads these dies will keep COL from increasing under recoil. I think the OP has other issues.

 

[Obturation]

I've heard the fcd problems and others have no problem, it's an inexpensive die set that can swage down things it shouldn't. Or not, I think the tolerances are slightly varied depending on the individual die. You'll know if you're swaging as it enters the fcd, if you get one bump of resistance when the case exits the die, you've over crimped and buckled the case . I can't see this being the OPs issue, if anything the lee die will put a very heavy crimp on any case I've used them on without a problem.
I can't guess how many 357s I've loaded (at least 1/100th as many as whoever has loaded the most on this forum-thats a lot ). I've never had one with no neck tension, once pressed you shouldnt be able to move them at all by hand. I've got to say defective/mismarked/incorrect die or completely incorrect bullet. I just can't imagine it being anything else.

ETA: can you insert a bullet into a new unsized case by hand?

 

[Trashyshoots]

Are you using .355 bullets or .358 bullets?

 

[DukeConnor]

Too much crimp. See if you can spin the bullet without a crimp.

 

[RealGun]

Assuming the dies are right, either the bullet is undersize or the case wall is thinner than the standard for which the dies are designed. It would be very telling if there is little to no resistance when expanding. That would be a thin case wall. I always sort head stamps and have only a few I favor. I do think you should measure the case before and after sizing to make sure that die is doing its job. You can also use a cartridge gauge to check for a suitable OUTSIDE diameter. The INSIDE is still suspect.

 

[Glockula]

Well....we all want to know what projectile it is. I personally want to see you resolve this. It doesn't sound right.

I crimp how you aren't supposed to. I crimp and seat in the same step with my Lee seating die. This is in trimmed(just once) random .357 brass. This includes starline that I bought new 8 or so years ago. Just enough roll crimp to help feeding in the lever action. I doubt it adds much tension on the projectile.

 

[rfwobbly]

Too large of an Expander. The Expander should be several thousandths smaller than the bullet diameter.

 

[edwardware]

OP must be loading tube. No benefits on crimping for a six shooter.

Other than a heavy crimp being necessary for most magnum powders to burn consistently, and preventing inertial pulling and a jam.

I like the collet rifle crimp dies, I was unaware they had them in pistol.

They don't. They use the same name for a post-sizing die that frequently ruins cast-bullet ammo by undersizing the bullet.

@Olon : you need a micrometer or a caliper, and a few minutes of measuring. Your tools, your bullets, or your technique is wrong.

First question: after seating, before crimping, how's your neck tension? It should be high.

 

[243winxb]

Take OD measurements of the brass during the reloading process. From fired, to reloading. Start to finish.

I am currently loading 357 mag with RCBS carbide dies from the 1970s. Also using 100 new Starline brass. My home cast bullet mics at .3581"
When i seat the bullets, i can feel a change in seating pressure. This tells me the wall thickness of the brass is not consistent. But i can not spin any bullets.
https://leeprecision.com/lee-collet-style-crimp-die/

 

[Walkalong]

Could be the sizer is too small (Won't work with the thinner walled cases like RP). Could be the expander is too big. Could be to much flare. Could be too much crimp on longer untrimmed cases buckling the case slightly ruining neck tension.

I use range brass for .357 Mag and the case lengths are all over the place between brands, so I trim it all to start for consistent crimping. With my plinker loads it lasts a very long time. With my full power loads you need to trim again after a few firings with some cases. Always chamfer & deburr after trimming.

 

[Demi-human]

Even if the case is completely unbelled, I can seat a lead or plated bullet without shaving and no matter how tight I crimp, the bullet usually can spin.

If that means the expander wasn't used at all, the sizing die may be too large. Not putting enough neck tension in the first place.

The expander may be doing just that without flaring the mouth. It may be too large as well.

Check both these measurements, as well as the bullets.