.357 crimp problems

[VrockTDSaz]

Do your other dies have this? Might be the problem??

Yep, that's the one.

 

[forestswin]

Vrock, seat all your rounds following the Hornady instructions for seating without crimping. Then crimp all your rounds in a second step, adjust the crimp per the instructions, making sure the seating stem is all the way up , not touching the bullet. You can seat and crimp in two steps, with the one die.
What are your case lengths?? They should be between 1.280 and 1.290 inches.

 

[VrockTDSaz]

Vrock, seat all your rounds following the Hornady instructions for seating without crimping. Then crimp all your rounds in a second step, adjust the crimp per the instructions, making sure the seating stem is all the way up , not touching the bullet. You can seat and crimp in two steps, with the one die.
What are your case lengths?? They should be between 1.280 and 1.290 inches.

That's exactly what I'm going to do. Two different steps.

Some of the brass is as short as 2.75. I'll sort these out.

 

[243winxb]

The case mouth and bullet must enter the alignment sleeve. If there is to much bell/flare, could the sleeve sit on top of the case mouth? Trim length would make a difference. Could be why one seats ok, and the other doesnt.

 

[forestswin]

Well then, did the 2cases on the right, buckle from just seating the bullet? You mean 1.275"?yeah sort them out.

 

[WestKentucky]

What kind of pressure are you using to crush cases like that? I have had stickers that I have had to put a pipe on my lever to free and I have never seen a case crush, even when intentionally pushing a sticker further in just to force it to move, and that was with a 3' cheater pipe.

 

[kilibreaux]

I'm having problems with crimping my .357 rounds. I'll get one round set up perfectly, and the next will over crimp and be bulged and not fit in the chamber. I'm using the Hornady dies with the seater and crimp in the same die. I've done the seating and crimping in the same die many times in the past. Just never with .357 magnum.

I'm assuming the problem is that the brass I'm using is different lengths. Though I've never had that problem with other calibers.

Is .357magnum especially sensitive changes in case length when crimping?

Would getting a separate crimp die solve the problem, or would I still have to trim all the brass? I don't trim handgun brass, is there a way to avoid it?

High pressure cartridges such as the .357 Magnum "stretch" their cases more than low pressure rounds. For this reason, the cases should be trimmed on the first reload to even them up.
You can also use a Lee Factory Crimp die which does not require that the cases be perfectly even.

 

[Walkalong]

The Lee FCD for rifles is completely indifferent of case lentgh. The FCD for pistols crimps like other dies, but unlike those dies the the crimping part is "suspended" by an o ring, which does give it a little leeway. I certainly agree with trimming .357 cases the first time around, but some people never do.

 

[VrockTDSaz]

What kind of pressure are you using to crush cases like that? I have had stickers that I have had to put a pipe on my lever to free and I have never seen a case crush, even when intentionally pushing a sticker further in just to force it to move, and that was with a 3' cheater pipe.

Not much pressure at all. Certainly, didn't feel like much more then a crimp. The funny part is that the cases are not "uniformly" bulged.

In the past, I have accidentally run a .357 case into a seat/crimp die that was set for .38. It crimped the heck out of the round, but didn't crush the case or make it bulge. Which is why I don't it's being caused by over crimping.

 

[buck460XVR]

Either the seating stem is adjusted wrong. (Too high up), or if there is no adjustment left on it, the die is down too far.

Yeah, somethin' else is up as I see little evidence of a crimp on any of the rounds in the pic. Also, for the force needed to buckle the cases like that, you'd think you'd see some deformation of the soft lead on the bullet by the seating die.

 

[Walkalong]

Well, it's hard for the crimp die to move the case mouth in when there isn't a cannelure in that spot, and I do think I see a little sign of it trying. I haven't seen buckling like that for other reasons. I am 99% sure it is trying to crimp before the bullet is seated far enough.


Adjust the die body so that it is 1/4" above the shell holder or plate. This will insure no crimp is happening. The adjust the seater stem down until you get the bullet seated to the point where the case mouth is in the middle of the cannelure. Then screw the seater plug all the way up. Then start adjusting the die body down until you get the crimp you want. Set the lock ring. Now take the round with no crimp but a bullet seated to the right spot and run up into the die. Then screw the seater plug down until it hits the bullet. Adjust it down 1/8 turn more and tighten. Now try seating and crimping a bullet at the same time. Tweak from there.

 

[buck460XVR]

In the pics shown, the difference in where the bullet is seated and crimped correctly and the case at the right that is noticeably buckled is much greater tho than any possible difference in case length. It's hard to believe one case in the batch would seat and crimp so well and another with the same die adjustment would buckle the case when the bullet was so far away from proper seating. The long cases in .460 are prone to buckling when seating and crimping in one stage and cases aren't all the exact same length, but they still result in a similar OAL. That bullet on the right is a long way from being the same OAL even tho it's buckled considerably. How much powder is in the case?

 

[Walkalong]

In the pics shown, the difference in where the bullet is seated and crimped correctly and the case at the right that is noticeably buckled is much greater tho than any possible difference in case length. It's hard to believe one case in the batch would seat and crimp so well and another with the same die adjustment would buckle the case when the bullet was so far away from proper seating.

True. I assumed (whoops) that he had seated a bullet with no crimp, then tried to do both at the same time. Could be wrong of course. If the same setting produced both rounds, your right, something else is wrong. Case mouth catching on something? Dunno.

 

[buck460XVR]

True. I assumed (whoops) that he had seated a bullet with no crimp, then tried to do both at the same time. Could be wrong of course. If the same setting produced both rounds, your right, something else is wrong. Case mouth catching on something? Dunno.

I can't believe the Press would bottom out with the round on the right in the pic because of the OAL shown....if the die was adjusted the same as the round on the extreme left. Even if the die was catching on the case mouth, how would the press bottom out? Only time I have seen a press bottom out without bullets being seated properly like that, was when there was an overcharge and the compressed powder pushed the bullet back outta the case. But one would think that much pressure again, would have deformed the soft lead on the tip of the bullet.

 

[Handgun Shooter]

Try backing off your case mouth flaring.

 

[VrockTDSaz]

Update: I pulled the die apart and cleaned it.

1. has almost no crimp, just enough so it'll fit in the cylinder.

2. Is rolled a little into the cannelure. It has a slight bulge about halfway down the case.

3. Has the most crimp, but I don't think it's excessive. The case has a substantial bulge around half the circumference.

I went ahead and ordereda separate crimp die anyway.

 

[Walkalong]

If that is not from over crimping, I'm stumped.

 

[VrockTDSaz]

If that is not from over crimping, I'm stumped.

I can live with the amount of crimp in the first round. Do you think its enough?

 

[WestKentucky]

I would cut a case and measure thickness. You may have a bad batch of brass. If it wasn't lubing properly as the blank was extrusion stamped then it may have very inconsistent case wall thickness as in very thick top and bottom but thin in the middle. I would certainly cut the crushed ones and measure thickness near the crushed area...unless it's mixed headstamps in which case I'm baffled.

 

[Walkalong]

Do you think its enough?

If you do not have a problem with bullet creep, and it shoots well, yes.

Another thing to consider is the cannelure. A poor cannelure (No depth) will not allow a very good crimp.

 

[VrockTDSaz]

If you do not have a problem with bullet creep, and it shoots well, yes.

Another thing to consider is the cannelure. A poor cannelure (No depth) will not allow a very good crimp.

That's a good point about the cannelure. I'm beginning to suspect it may be the bullet I'm using. I intentionally over crimped a plated round (way, way over crimped it) and the case didn't buckle.

 

[Walkalong]

Yep, the soft bullet let the case mouth roll into it.

But more importantly, look how far down the scrape from the crimp ledge is. It should not be any farther down than the bottom of the curve on the crimp.

 

[RainDodger]

A roll crimp depends on one item: case length. Obviously, all cases must be an identical length if you are using a roll crimp.

However you do it, you must first ensure case lengths are equal, and then simply adjust the die's height to crimp it the way you want. It really is that simple.

If there is a question about whether you should be using a roll crimp for .357, yes you should, providing there is a cannelure on the bullet to roll the case mouth into.

 

[Blue68f100]

It looks like your doing the crimp before the bullet is seated deep enough. Your case mouth should be toward the top of the groove. Doing it before the bullet is at proper depth will buckle the brass. There is no where for the lip to go.