Loading 357 sig

[aplthird]

Hello,

 

I am looking to load for 357 Sig.  I have loaded for 45 acp,10mm , never a bottle neck

cartridge.  I am using a Dillon 550.  What are some recommendations  for dies setup?

I know the powder drop will flare the case neck.  I have always seated and crimped in two

stations and would like to continue that.  Can anyone recommend what manufacture

to use for the sizing , seat and crimp stations. I already have the case holder for the

10mm so I just need to get the powder drop funnel for the powder station, assuming that

I need one for 9mm there

Thank you.

Tony L

Edited January 16, 2023 by aplthird
more info

[aandabooks]

When I load .357sig I size with a .40 die in a batch then go back and put a .357sig sizing die in to actually load.  This keeps from having to lube the brass.  My dies are Hornady and load on a Hornady LNL.  I seat and crimp in separate steps on station 4 & 5.  When I load I use 135gr S&S Casting bullets due so the long straight wall to crimp to.

[sharko]

I processes (size) my brass separately and like the above I use a 40 die followed by the 357Sig die for the same reason. I use the Dillon carbide dies.

For the powder funnel I use a Photo Escape 9mm so as not to over expand that short neck, then seat and crimp separately with Dillon dies. 

[Banacek]

I start with the Redding .40 buldge buster and then use the .357 SIG dies.  I have used Hornaday one shot to avoid any sticking in the dies but that is probably overkill.  I seat and crimp in separate steps as well and then do a crimp test to make sure no setback occurs.  

[dansedgli]

I just use 357 sig dillon dies.

 

Mr Bulletfeeder 9mm flare die in the powder drop. 

 

You should lube your brass anyway. I use hornady one shot.  

 

Plot twist: I mainly use 40 cal brass because it is free. There are some sig cases in there but not many. 

Edited January 16, 2023 by dansedgli

[aplthird]

Thank you all for all your help.

[plinker625]

Use powders that fill the case that can help with bullet set back.  Accurate #9 is one.  VV quit making N105 it was another option. 

 

Very few bullets are "meant" for the 357 Sig  Montana Gold and Speer are two places to look.

 

I have Wilson case gauge and Dillon Dies.  The Redding die is call G-RX die in both Steel and Carbide, not a Bulge Buster set up from Lee.

 

[aplthird]

What about primers ?  Seems I have alot of free small magnum pistol primers given to me.

I have read people have been using  reg and magnum

Edited January 18, 2023 by aplthird

[aandabooks]

4 hours ago, aplthird said:

What about primers ?  Seems I have alot of free small magnum pistol primers given to me.

I have read people have been using  reg and magnum

Doesn't really matter.  About 20-30 FPS difference.  Maybe if you are going with a slower powder like Accurate #9 then a magnum might burn a little more fully before the end of the barrel.

[9x45]

I load once fired 357SIG on a  550 with Dillon dies, except for the Lee floating collet die. This setup does not require trimming of the brass as the Lee die allows about a +/-. 005" change in length. Lubing with Dupont Dry film lubricant. For the 125's 8.4 BE-86, for the 147gr, 7.6 BE-85

 

 

Edited January 19, 2023 by 9x45

[MikeBurgess]

the best thing I found when loading 357 sig was the Lee factory crimp die, it is a collet type crimp that closes as it hits the case plate so its crimp works the same regardless of the case length 

[sharko]

I've had good luck with #7 in both 10mm and 357Sig. And the 357Sig seemed to really like the .356 125gr HAP's. Don't know if it was just the Barso barrel in my 229 but this was 10 rounds @25yds from my Ransom rest. My 10mm DW Silverback produced the same results.

 

 

[aplthird]

I picked up the Lee die for crimping  One a side note are the

diameters of cast and jacketed bullets the same for this caliber.

I  found one individual who said that cast should be .356 and

jacketed .355.  The gun I picked up is a SIG P320X.

[anachronism]

My P320 prefers .357 sized cast bullets, and seems to feed any bullet design I throw at it without a bobble.  My favorite powders are AA #7, AA #9, and 800X (now discontinued). I size the cases first by pushing them through a gutted LEE carbide Factory Crimp die to make sure we have full-length sizing, then sizing a second time in a standard Hornady sizing die to that care of the neck. It takes longer to tell about it than it does to actually do it. So far it's pretty standard stuff, and I also use LEEs collet type crimp die as described above. Look for 9mm bullets with the greatest parallel shank length since 357 prefers short nose bullets for feeding. My personal favorite cast design would be hard to find if you don't cast your own, it's a design called a "Ranch Dog" 135 gr that has a pretty large meplat and has a well deserved reputation for accuracy.