357 SIG; Learning the Ropes

[kcofohio]

First, I'd like to thank members here that posted their tips in other threads on how they load for this cartridge. I don't remember all the names, but I appreciate the inputs.

I never had considered the 357 SIG as one to be added to the collection, but, here it is now. As the saying goes, "One thing leads to another".

At the suggestion of multible members, I use a 40/10 carbide sizing die before using the FL 357 SIG sizing die. And chamfer the case mouth slightly, about .010-.015" @ 30 degrees.

My first set of dummy rounds, 20 of them, showed promise of only losing about .002-.004" on the OAL when chambering. But my first reloading session, I got some bullets that wouldn't line up when seating. When seating, as the ram is being raised, I hold the bullet on the case mouth until the bullet starts entering the die. As the ram raises, I spin the casing to let the bullet align with the case mouth and the die bullet stem. What I found was that some casing mouths were slightly deformed, even after both sizing processes.

So my 1st attempt was carbide 40/10 sizing/deprime, FL sizing/deprime, prime, off line powder charge, then bullet seating.

2nd set-up, that is working better now;
Chamfer case mouth, size with carbide 40/10/deprime, prime, Lee powder through 357 SIG charging with the Lee Autodrum, now the FL 357 SIG sizing die, and bullet seating.

The 1st attempt I was wanting to avoid flaring the case mouth, as I felt that would take away from the neck tension. But after I seen some case mouths having slight bends or nicks, I figured the powder through die would ensure a truer case mouth for easier bullet seating. Then I could FL size them and have maximum neck tension per the quality of brass. After FL sizing, the case mouth I.D. is about .348" per a decent cheapo calipers.

It definitely is a different set-up to work than most other handgun cartridges. BTW, I'm using the LCT press.

 

[CMV]

I did mine on LCT as well. I had difficulty at first with neck tension too. I used all Lee stuff and I know the dies you have will work

What I ended up doing was setting the powder thru expander die (used Lee Pro AutoDisk too) to not bell the mouth at all. I put a good chamfer inside the case mouth with a standard chamfer/deburr tool - not a VLD style. Not so much I was losing length, but more than the couple partial twists you'd do for something like a freshly trimmed .223 case. Then set the seating die to not crimp at all, just get the bullet where it needs to be. No FCD.

I didn't really like the excessive inside mouth chamfer, but I like the neck tension I got that way. It was a little slower/more difficult seating bullets, but jacketed bullets (like the Montana Gold) had no issue. Plated or cast would probably shave but never tried those.

I had read smart guys like RC Model say things like "no amount of crimp makes up for poor neck tension" and never really understood what that meant until I messed with 357SIG

But anyway, maybe my way will work for you. I spent a lot of time trying to bell mouth a little or just at the very tip to make it easier to seat the bullet. And tiny little micro-adjustments chasing getting it right. But no matter what, I could push hard against my bathroom scale and push the bullet into the case around 25-35 lbs. I didn't get better neck tension until I figured out a 0 belling, 0 crimp way & then was happy with the results.

 

[CMV]

Oh...and are you having the seating issues on just the nickel brass or the yellow brass too? Either way, needs a fair amount of lube for sizing and some inside case mouths. Real similar to .223 - same amount of lube, a little touch of Unique case lube inside about every 10th mouth - doing it that way, I don't remember getting the out-of-round mouths you are describing.

 

[kcofohio]

Oh...and are you having the seating issues on just the nickel brass or the yellow brass too? Either way, needs a fair amount of lube for sizing and some inside case mouths. Real similar to .223 - same amount of lube, a little touch of Unique case lube inside about every 10th mouth - doing it that way, I don't remember getting the out-of-round mouths you are describing.

I should have describe them more as extraction dings. Maybe from a certain gun.
They were of the brass type. The 1st attempt was brass with XTP type bullets. I loaded up 50 with the Montana Gold later in brass with no problems.

 

[cfullgraf]

Over the past 10 years or so, I have loaded some 357 Sig but I have loaded lots of 38/45 Clerke, another bottle neck pistol cartidge, over the past 20 to 30 years.

I just use a full length sizer die to size the case. I have not seen a need to use the 40 S&W die to size the body of the 357 Sig cases before sizing the cases in a 357 Sig sizer die. Same with the 38/45 Clerke. I just use a 38/45 Clerke sizer die to size the cases as opposed to passiong the cases through a 45 ACP die first.

But, my guns do not have chambers that bulge the brass and require special treatment before sizing.

As far as neck tension, my neck expander dies do not expand the neck except for the flare at the case mouth. I run the cases through the progrewssive press with the sizing die and neck expanding die in place. I then clean the cases setting them aside for a future loading session. Neck tension has not been an issue. I taper crimp the cartridges at the end of the loading process to remove the flare from mouth expansion step.

When loading the cases, the powder drop does not do anything to the case mouth, it just directs the powder into the case.

This method tends to bypass some of the advantages of a progressive press, but if it loads quality rounds, it beats re-work fixing cartridges not loaded to specification.

 

[JimKirk]

No belling & no crimp for me !! Chamfer the inside ....

I run my cases through the Redding G-Rx dies (.40 S&W) mine is steel .... I put my brass in a gallon Ziploc bag and couple sprays of lanolin/alcohol mix .... then run through a 357 SIG RCBS sizer ....

60% of my brass is nickle... easier to find ....

Chamfer is a must with this cartridge .... at least in my experience...

 

[cfullgraf]

Chamfer is a must with this cartridge ...

I agree although I have never had luck chamfering the case mouth without some belling of the case mouth. I have trouble getting the bullet to seat without damaging the case.

If one has success with chamfering without mouth belling, great. It will definitely help with bullet tension in the case.

For me, chamfering the case mouth does help the bullet seat and also minimizes/eliminates shaving of the bullet while seating. A bit of flaring the case mouth helps me seat the bullet.

Besides 357 Sig, I chamfer the case mouth of any case that I reload. It helps with seating the bullet as stated above.

Bottom line, chamfering the case mouth is another "tool" to be used to assist in reloading.

 

[vaalpens]

I am also in the "no chamfer" camp. The key for me is sorting my 357sig brass by length. This allows me to be precise with the belling and crimping, thus no setback so far after 4k rounds. I did do a side by side testing for neck tension between a few chamfered and non-chamfered dummy rounds, and could not detect any difference. The only difference I detected was that it took a bit more effort to line up the bullet during the seating step. As long as you keep the expanding to a minimum and load quality bullets, chamfering should not be required.

 

[kcofohio]

Well, you all have given me some other ways to try out.
As an ol journeyman once told me in my apprenticeship, "You do it my way, another journeyman will have you do it his way. In the end you figure which works best for you."
Some things just never change.
Thanks everyone for your input. Much appreciated.

 

[Mowgli Terry]

I use mostly Starline brass for the 357SIG. Loaded on a 550 it's necessary to have things set right. My sizing die is a Lee and works very well. The Dillon powder funnel must be set accurately to only allow the heel of the bullet to enter case mouth. I use the Dillon crimp die. I have used this arrangement successfully to load both jacked and lead bullets. To me, some kind of taper crimp dies is essential to making good 357 SIG ammo.

 

[kcofohio]

I did mine on LCT as well. I had difficulty at first with neck tension too. I used all Lee stuff and I know the dies you have will work

What I ended up doing was setting the powder thru expander die (used Lee Pro AutoDisk too) to not bell the mouth at all. I put a good chamfer inside the case mouth with a standard chamfer/deburr tool - not a VLD style. Not so much I was losing length, but more than the couple partial twists you'd do for something like a freshly trimmed .223 case. Then set the seating die to not crimp at all, just get the bullet where it needs to be. No FCD.

I didn't really like the excessive inside mouth chamfer, but I like the neck tension I got that way. It was a little slower/more difficult seating bullets, but jacketed bullets (like the Montana Gold) had no issue. Plated or cast would probably shave but never tried those.

I had read smart guys like RC Model say things like "no amount of crimp makes up for poor neck tension" and never really understood what that meant until I messed with 357SIG

But anyway, maybe my way will work for you. I spent a lot of time trying to bell mouth a little or just at the very tip to make it easier to seat the bullet. And tiny little micro-adjustments chasing getting it right. But no matter what, I could push hard against my bathroom scale and push the bullet into the case around 25-35 lbs. I didn't get better neck tension until I figured out a 0 belling, 0 crimp way & then was happy with the results.

The Speer nickel brass and the Montana Gold bullets I got off you work really well. The bullets fed really well and had plenty of bearing surface beyond the case mouth. And the FL sizer die makes for a tight neck.

 

[kcofohio]

I went to the range yesterday. I worked some loads up using CFE-P and Longshot.

I think I was a bit overaggressive with the case mouth chamfer on some. I had a split neck on a piece of brass, and I'm thinking I thinned the mouth to the point that it weakened it. So I will start to just break the edge and touch off barely with the powder through die.

 

[kcofohio]

60% of my brass is nickle... easier to find ....

I have actually found that to be the opposite for me. At my club, there are a lot of aluminum casings lying around that makes for nickel camouflage.

 

[JimKirk]

I have actually found that to be the opposite for me. At my club, there are a lot of aluminum casings lying around that makes for nickel camouflage.

I guess it lucky ....I have the only 357 SIG and zero so
Aluminum ....