357 sig handloaders wanted

[danthearmyman]

I had been using RCBS dies for some time now, and after I added a new handgun I found that they do not bump the shoulder back at all. My shoulders were .694 and are supposed to be around .64. Now I had a machine shop mill off .050 on the die. It sets the shoulder back, brass chambers, BUT now it shaves the brass on the bottom 1/8 of the case. Im at a loss on how to fix this, and ready to just try a different manufacturer.

What dies are you using, and where are your shoulders after resizing?

 

[Elkins45]

I did the same to my RCBS sizer die, but I eventually just ended up buying a set of Lee dies so I could get a powder thru expander.

A very clever technique I learned here is to size the body of your 357 Sig cases using a 10mm or 40 S&W carbide sizer, then resize just the neck in a regular 357 die. This might fix your shaving problem, but there's something cheaper you can try first. Try using a cone shaped grinding stone or even just some sandpaper to 'break' the sharp edge on bottom of your die. That might fix it.

 

[clocker]

I've used both the Lee and Hornady die sets. Funny story: last night I was loading up a new group. After a dozen rounds the cases started to have streaks. I pulled the size die and found that it had what looked and felt like scratches. Sonofa! So I lubed up some cases and set up the Lee sizer that I had gotten as a backup. Well today I was ready to call Hornady up, but figured I'd check the die one more time. Turns out that some of the brass had smeared onto the steel and made it look like scratches. It polished out fine and now both die sets are whole.

Your problem sounds like the machine shop may have left a sharp edge at the bottom of your die. Check it with your finger to see if it is sharp. You can break the edge with some fine sandpaper, dremel tool or a machinist's deburring kit. The bottom of the die should have a nice radius to make sure that the case feeds well and does not shave brass.

I've never measured the shoulder with any of my cases. Chamber test or a case gauge are the tools that I usually use.

 

[david_r]

You measured them in that gun to be at .640? How exactly did you measure that? I resize with a lee and just bang through them. Resized brass show acceptable headspace in my glock. If I can get the bullets started somewhat straight, after crimping they all fit and go bang in my glock. Tell me how to measure to the middle of that little shoulder with a pair of calipers and I will go measure mine.

What you did when you had the bottom cut down is you eliminated the smooth radius between the inner diameter of the die and the mouth of the die. That is my guess as to why you are shaving brass. That radius is what does the body resizing. The largest diameter of that mouth should be larger than the largest diameter on your brass. A guy could round it off with any number of tools if he didn't have a way to grind the radius back in there.

 

[ReloaderFred]

You should have milled off a few thousandths from the $5.00 shell holder instead of the $25.00 die. Like the others have advised, break the sharp edge of the die and all will be well.

Hope this helps.

Fred

 

[danthearmyman]

I thought it was the sharp die edge, and headed back to the shop and had them put a chamfer on it, still shaving. Going to hit it with some sand paper tomorrow (all I have is 80 grit now) and see what comes of that.

I didn't measure in the gun, but the factory ammo I do have (very little) chambers with the shoulder at .649 actually. The RCBS die was putting them at a .694.

I would have done the shellholder, but others have complained that they went too thin and the shellholder would give way, and result in stuck brass. Not that big of an issue, bit I figured why not try the die? It was worthless how it was anyways.

I'm already sizing in a Lee carbide "undersized" 40 s&w sizing die. I just need to move the shoulder back.

When I measured I just went for the second bend from the top, or the part where the slope stops. SAAMI publishes specs for the neck, should angle, length to first bend, length to second bend, etc. I kept getting small variations (+/- .005) probably due to bad form, but I was still .050 out of spec overall.

 

[david_r]

dan,

I am very surprised that any die mfg would have their should so far out of specification. BTW, what you are measuring isn't the shoulder but can be used as a datum for discussion. The shoulder is the .670-.677 measurement where the case diameter is .4059 in the drawing. That is why I was wondering how you were measuring the shoulder.

I use Lee 357sig dies with shoe wax to resize. I rubbed a resized case on the concrete to try and determine where that radius starts. Near as I can tell, from the base of the shell to the start of that radius is around 0.652, give or take.

I am also baffled how you are shaving brass after running the body through a Lee U die. You would think that the sig die would only be kissing the brass at that point. A chamfer is still going to have a sharp angle on it so I would definitely try to ease that.

I hate it when people tell me to check what I already checked but, I would look elsewhere. FGuffery would say, did the press beat the brass or did the brass beat the press or something to that effect. IOW, are you absolutely sure the shell plate was in contact with the die at the end of the stroke? I guess that's water under the bridge since you've already modified the die to get the shoulder where you want it to be.

This is the worst part of the current lack of inventory. When someone gets a suspected bad tool, they are practically forced to try and modify it instead of exchanging it if they want to reload in the next month.

 

[danthearmyman]

This is what's happening...

Mic'd out my shellholders, and it would only leave me at .019 on one and .017 on the other for material left. Don't think that would be enough... .025 and I'd try it, but I think I'd just be wasting a shellholder.

 

[david_r]

If it was my 357sig, I would resize to headspace off the shoulder and I would be using my barrel to determine where that shoulder would be. realguns.com has some really good articles on the 357sig and headspacing.

 

[clocker]

Hmm. Can you try sizing a case without using the 40 S&W die first and see if it looks better? What does the case look like with only the S&W sizing?

That case doesn't look right for sure. Not to second guess you, but can you verify that the RCBS die is marked for 357 Sig?

 

[danthearmyman]

The only pistol round I reload is 357 sig...also the only one I shoot. If I run it without the 40 sizing die first it shaves the entire case...it's pretty bad.

Probably going to the machine shop tomorrow and milling out that last 1/8th inside the die so it doesn't contact. Hopefully when it bumps the should it doesn't crush the cartridge

 

[Elkins45]

That case definitely looks odd. What gun are you shooing them in?

I'm thinking you either have a bad die or a bad chamber.

 

[danthearmyman]

david...

The brass chambers in my barrel now, I was about .04-.055 out before I had the die cut back. I'm running 2 different handguns (S&W MP and SA XD). The XD has a shorter (shoulder isn't as far forward) chamber than the MP, and the die was not contacting the shoulder at all. I ran the die all the way down to where I was actually camming over pretty firm on the press, and still getting no movement in the shoulder.

When I get home later today I'm going to sand the chamfer a bit and see if I can get rid of the shaving. If not I might just mill out the part that is shaving (bottom 1/8th) as all I need is for the die to move the shoulder. Just scared if I do that that when it bumps the shoulder, the wall might buckle.

The die seems to be shaving the part that the lee sizing die doesn't quit hit as well, and I have a bulge buster kit on the way. When that shows up I'll see if that resizes it to stop the shaving before I make anymore cuts.

So, 600 wet/dry sandpaper, elbow grease, and another go

 

[danthearmyman]

David...

chucked the die into a power drill, 600 grit wet/dry for 15 minutes, and BAM....

no more shaving! Rounding out the chamfer did the trick! Thanks everyone for the help!

 

[david_r]

Excellent news. Really glad you got it worked out