Author Topic: re: reloading 357 sig question (Read 3062 times)

Type99 · « **on:** July 05, 2004, 01:54:54 AM »

Hello...

I decided to buy a P226 in 357 sig, and forego a 357/.40 S&W combination. And I am glad I did.

Accuracy is tops from the new pistol, which is hardly surprising based on my previous experience with Sig products.

I am anxious to start reloading the 357 sig. I plan to use Accurate #9 powder and 124 gr Hornady XTP bullets. In checking one Internet loading table, the load mentioned using #9 powder had CCI 400 primers listed. Is that correct? Those are rifle primers! All the other loads listed CCI 500. I thought it must have been a mistake. I'm a little confused.

Do 357 sig loads use CCI 400 primers? Or would CCI 500 be the appropriate primer to use?

Thanks in advance,
Gary

dave375hh · « **Reply #1 on:** July 05, 2004, 02:21:54 AM »

99,
Small pistol primers are what to use, not sm rifle's. I've found that AA#7,
and Alliant Power Pistol are the best for my loads. AA#9 takes a compressed load to equal the vel. of these other powders. Compressed loads are not a good idea in a cartridge that can have bullet pull problems.

What ever reloading dies you decide to use get a Redding taper crimp die and crimp in a seperate operation. You have to taper crimp because the .357 SIG headspaces on the case mouth not the shoulder(a mistake in my opinion). Using Redding dies and an older Dillon press(RL450B). I've had no problems with bullet creep or set-back.

Go to www.reloadammo.com The data on this site is what got me started, Thank you M.D. Smith.

Somerled · « **Reply #2 on:** September 22, 2004, 11:17:28 AM »

Use CCI-500 primers.

One has to be careful selecting bullets for the .357 Sig. I use the 124 grain Golden Sabers Remington made specifically for the .357. They have a long bearing surface. It is difficult to avoid setback with some bullets geared for the 9mm Parabellum.

I use the Redding dies as well. Even though the .357 Sig does headspace on the case mouth, it needs a firm taper crimp. You'll get it with the setup mentioned in the previous post.

The .357 Sig is a blast. I have been tempted to get a barrel for my Browning Hi-Power .40 S&W.

Type99 · « **Reply #3 on:** September 23, 2004, 12:43:38 AM »

Hello...

I have not had any problem with the 124gr. Hornady XTP bullets I have been loading. I use Accurate #9. I have not noticed any set-back problems. I have Lee dies, and use the CCI 500 primers.

I agree...the Sig .357 is alot of fun! Reloading these rounds is very easy.

Thanks,
Gary

Savage · « **Reply #4 on:** October 23, 2004, 04:23:23 PM »

Really? The .357 Sig headspaces on the case mouth? I've never known of a bottleneck case to headspace on anything other than the shoulder. With the exception of the belted cases.Guess I have a lot to learn about the cartridge!
Savage

calvon · « **Reply #5 on:** July 09, 2006, 06:01:17 AM »

I have a P229 with .40 S&W and .357 Sig barrels. I shoot homemade cast in both of them (180 gr in the 40 and 160 gr in the .357) and use a single charge weight of AA#7 for both.

Agree with the guy who says to get a Redding taper crimp die for the .357. The short neck, with its limited grip area, needs to be crimped and the Redding die does it best.

Whether the .357 headspaces on the mouth or the shoulder can be argued. I don't think it makes two hoots of difference but I suspect, without knowing for sure, that it headspaces on the shoulder, especially when using reloads.

M60ACE · « **Reply #6 on:** July 24, 2006, 08:14:26 PM »

All of the resources i have read, and in my 20+ years of reloading, Ive not heard of a non belted rimless bottleneck case headspaceing on anything other than the shoulder. The 357 Sig does headspace on the shoulder. This however has no real bearing on the original post.
First concerning the primer. Check for data that uses a small pistol magnum primer, as the powders mentioned (AA7 & AA9), are spherical, or "ball" powders. Unlike flake or stick powders, these powders are typically loaded to a higher case density. The "ball" powders have very limited space between the granules, and it "may"(schools of thought do differ) take a hotter primer to thouroghly ignite the powder. The powders mentioned are on the slow burning side of the powders used for pistol, thus another reason for the hotter primer, to get the powder to fully burn in the 4.4 inch barrel.
Again , i will concede there are many schools of thought on this, but with powders such as 296, H110, AA9, the powder mfg'rs usually recommend a magnum primer.
Now for the crimp. You will need a good solid crimp with the slower powders, especially AA#9. This is for consistancy of the pressure curve, a tighter crimp will aid in the consistant burning of the powder, and the pressure curve. Again, with powders such as AA9, H110, and Winchester 296, The powder mfgs. suggest a "high bullet pull" or tight crimp.
AA5 or AA7 probably wont need as tight of a crimp as #9. The same would be true of say, Blue Dot which is a flake powder.
I hope this helps. BEST OF REGARDS TO ALL------Todd

Reed1911 · « **Reply #7 on:** August 17, 2006, 12:03:38 AM »

Okay, I'll bite

Unless the designers are lying about it, even though common sense says the shoulder, the .357 and the .400 CorBon both headspace off the case mouth. The 7.62x25 commonly headspaces off the mouth although it was not designed to, same goes with the 7.63 Mauser and .30 Luger. While it is a little hard to wrap our heads around it, when it comes to short auto pistol cases it is more often the mouth not the shoulder that is used.

Savage · « **Reply #8 on:** August 17, 2006, 01:49:06 AM »

Reed is correct as usual. Thanks for the enlightenment! I suspect that a lot of pistol cases are held against the bolt face by the extractor anyway, making case length and chamber depth a little less important.
Savage

Type99 · « **Reply #9 on:** August 18, 2006, 01:04:49 AM »

Hello ...

As original poster on this thread, I would hasten to add that I have been reloading .357 Sig for some time now, using only my Lee dies, and the powder/bullet/primer combination I mentioned. I have not experienced any problems whatsoever. Accuracy is superb. I have used both Hornady XTP and FP 124 gr bullets. The Lee dies crimp the bullet sufficiently for my purposes. I also find that standard small pistol primers ignite the AA#9 charge just fine.

Insofar as my experience, albeit limited, indicates, nothing could be easier than reloading the .357 Sig...

Thanks,
Gary

Savage · « **Reply #10 on:** August 18, 2006, 01:58:53 AM »

Type99,

Glad your process works for you! If it isn't broke, don't fix it------------

Savage

calvon · « **Reply #11 on:** August 23, 2006, 04:40:12 PM »

Well, gents, I'm going to try to wrap up the question as to whether a bottleneck pistol case headspaces on the mouth or on the shoulder. Common sense would dictate that whichever one, mouth or shoulder, that makes contact first will control headspace for that particular round. If there are variations in brass length and/or head to shoulder length it could be on the shoulder for one round and on the mouth for another.

And if neither one makes contact then the extractor will control it.