Loading 357 Sig - Canted in Case?

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Jul 22, 2003
New England

I'm trying to get my press (550B) set up properly for .357 SIG. I've loaded several rounds that show no pressure signs and seem pretty accurate, but a few of them are obviously canted in the Case. I've tried to keep the bell moderate, and the OAL is a little longer than normal (to avoid excess pressure).

Load = 124gr Montana Gold .355 (HP), 8.8gr HS6, Remington 1 1/2 Primers. Have used some Once-Fired Winchester, Brand New Winchester, and Once-Fired Speer Nickel. OAL = 1.142 - 1.145, Lee Dies in Dillon 550B.

Anyone else experineced this issue?

Thanks in advance,

The very short neck of the .357 SIG case requires that the bullet seating stem fit the bullet contour exactly to get proper alignment.

Might start looking there.

Also, many 9mm bullet profiles designed for the 9mm Luger cartridge will not work at all in the .357 SIG because the ogive slips in the neck so far there is little or no neck tension left to hold the bullet properly.
Might look there too.

You might try a seating die like the Hornady, with a sliding alignment sleeve to better align the bullet. I don't know if Redding makes a competition seater die in 357 sig.

I have not had good luck with Lee seating dies, especially with 7.62x25, a similar bottleneck pistol cartridge. The Hornady 30 Lugar seating die happens to work perfectly for it.

I don't know if Redding makes a competition seater die in 357 sig.

Unfortunately they don't.
The OP could try a Lee or Hornady seater.

I prefer truncated cone bullets over HP's in the 357 Sig.
I use Zero and Montana's 125gr. TC. which is specifically for the Sig.
Thanks for the replies

I took 3 steps that seem to have helped:

1) Backed off the OAL 5 thousandths to make sure the bullet seats to the "ledge" vs the tapered end of the projectile. I'm now loading at 1.145 - 1.148.

2) Reduced the bell slightly to limit the angle of seating entry.

3) I tightened down the sizing die about as far as it will go which influenced the neck size.

So far, seems to have worked well. I still have on occasional bullet that has a visible cant (probably 1-2 degrees) vs. 5 degree cants previously that had to be pulled and redone.

Thanks again,

1) Backed ... the bullet seats to the "ledge" vs the tapered end of the projectile. I'm now loading at 1.145 - 1.148.

I say you have the wrong bullets. The crimp should be on parallel shank of the bullet, with room to spare. Does Montana say these are the right ones for 357 SIG?
For most of my 357 Sig loading, I use the Berry's 124 grain Flat Point 9mm, or 124 grain Hollow Point 9mm bullets. They work great and have a short ogive, which is perfect for the 357 Sig. For really hot loads, I'll use the Speer Gold Dot 357 Sig bullet, or Hornady 124 grain XTP.

I inside chamfer each and every case for this caliber and it greatly improves bullet seating. I also make sure the seating stem matches the bullet profile, and if I don't have one that does, I make one.

Hope this helps.

the 357 sig cartridge is a problrm child! you must have the right componts to load this round corrrectly. I think you are using a 9mm bullet and need to get some made for 357 sig as other have showed you in previous threads. I find that nickle brass can be a problem do to spring back I like good old yellow brass. these rounds are like a mini rifle round doing them on a progressive may be hard. In the past i have used some primer water proof solition "ROYS" to seal stubborn cases. but if you take you time and chamfer the inside of the case neck just a bit it will really help seating the bullet. good luck!
I have loaded a lot of 357 sig rounds and haven't seen the problem you mention. I use bullets specifically made for the cartridge to account for the round's extremely short neck. I use montana gold which is a flatpoint and there is a speer gold dot for this caliber. Both work well in my p226
I'm on my 2ndK of Montana Gold 357Sig bullets and haven't had a problem since I switched to the. I use an RCBS Pro 2000 press and can do 300 in less than an hour with full control.
I use 800X, very slightly bell the case, look into the case after the powder drop, seat the M gold bullet with the taperd base and pull the lever. Make certain it is taper crimped and load away.
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