Reloading 357 Sig Question

[PCCUSNRET]

I'm getting ready to reload some 357 Sig and after resizing a few pieces of brass I noticed that the neck is nowhere near the size of a factory load(hopefully you can see from the photos below what I am talking about). I have turned the RCBS resizing die down till it touched the shell holder and then turned it another 1/2 turn. The area of the neck that will actually hold the bullet on the ones I have resized is only .095, where the factory load is .130. It just doesn't look like there is going to be much neck area to hold the bullet on the ones I am resizing. Am I doing something wrong or is this the way the RCBS die resizes this round? Thanks for your help.

 

[ReloaderFred]

Fisrt thing to do is try the sized case in your barrel and see of the shoulder has been set back enough for the case to chamber. If it will, then it's headspaced properly for "your" barrel, and your barrel alone. If not, then the shoulder needs to be set back further.

As I've mentioned numerous times in threads concerning reloading 357 Sig ammunition, there are actually two datum points in this caliber, the case mouth and the shoulder. If either one is too long, the round won't chamber.

You may have to try other shell holders, if you've got them. They do vary, just like any other machine part. If that's not possible, then you may have to do what I did and mill off several thousandths from the top of the shell holder so it will be able to push the case further into the sizing die.

Someone will come along shortly and tell you that you don't need to mill anything off the shell holder, or to grind some off the bottom of the sizing die. That's fine, but sometimes it's easier to fix the problem than it is to send parts back and forth between you and the manufacturer. I prefer to alter shell holders, since they're cheap. Sizing dies aren't cheap, and if you mess up the grinding job, the company most likely won't stand behind an altered die. You can always buy another shell holder, if needed.

Hope this helps.

Fred

 

[PCCUSNRET]

Fred,

Thanks for the info. I will check tonight to see if they fit my gun. If not, I will contact RCBS and see if their shell holder is the same thickness as the Lee. If it is thinner, then I will order a RCBS shell holder for this round. If it the same, I will try grinding down the Lee shell holder to allow me to bump the shoulder back some more. I may send the photos to RCBS and see what they have to say. I've found most of the techs at RCBS are very knowledgeable and helpful when it comes to sorting out problems like this. I can see that grinding the shell holder down would fix the problem but I would really like to know what is causing the problem to begin with. If it is using the Lee shell holder with RCBS dies then I'll stop doing it (never had this problem with any other Lee shell holder/RCBS Die combination). Thanks again.

 

[PCCUSNRET]

They fit the gun just fine. I'll try a few and see how they do. Thanks again.

 

[ReloaderFred]

As long as you get enough neck tension to hold the bullet, and the rounds chamber, then they should be fine. Lightly chamfering the inside of the case mouth will facilitate the bullet entering the case without belling the mouth.

Shell holders are "supposed" to be the same, but they aren't, even within the same brand. As long as they fall within the manufacturing parameters, they're considered "within spec".

You'll also probably want to use a powder that will be slightly compressed to help prevent bullet setback. I like Accurate Arms #9 for this reason in 357 Sig. It fills the case and gives excellent accuracy in both my pistols in this caliber.

Hope this helps.

Fred

 

[JimKirk]

As Fred said ... as long as they fit your chamber ... all is well ... you can sized too much and over work the small shoulder.

If you need to compare brass... do so with a once fired(in your chamber) ... look at the difference between it and sized brass... that will tell a better story ...

AA#9 works very well in my Glock 31 in 357 SIG... I also like 800X ...but it does not meter very well. I will trickle up metered 800X to get the loads I like ... because it shoots dang well and gives very high velocity.

Jimmy K