9x21, .356 TSW; Please explain differences.

[GooseGestapo]

I have gotten a S&W "Super-9" with 3 barrels. I got it primarily for the 9mm barrel to shoot in PPC competition. However, I'm not immediately familiar with the .356 TSW cart. I know it was a proprietary load for S&W Perf. Ctr back in the '90's and performance is similar to .357 Sig.

What I want to know is:
1. Can 9x23 or 9mm Largo brass be used instead of .356 TSW brass in .356 TSW barrel, and;

2. Can the .356 TSW be loaded using .38 Super dies ??

3. If any one has experience with the 9x21, would accuracy and flexibility of using heavier bullets justify the substantial extra cost of the 9x21 brass??

I have about 10,000 Win 9mm cases, 2,000 Starline, 1500 Fed. 9mm brass, and both .38 Super and 9mm dies, many moulds, ect.-

Wanting to know if I need to, and/or can justify buying additional brass or dies to use extra barrels. ( I know that 9mm Para. dies are used for 9x21)

 

[Jim Watson]

As I understand it from my reading, I do NOT have one;

1. .356 TSW is approximately a 9x21.5 so you would have to trim 9x23 Win or Largo to fit. There was one magazine article where the writer just used 9x21 and the .020" excess headspace "didn't make any difference."
Starline makes the brass, no need to improvise.

2. .356 TSW is a tapered case, same head and mouth as 9mm P so you would use those dies, not Supers.

3. Hanged if I know. The only use I ever saw for 9x21 was to get around the 9mm Major ban in USPSA.

I think I would try to sweet talk Starline out of a hundred each and load some just to see if one or the other barrel was enough more accurate than the 9mm P to make it worth the trouble.

 

[GooseGestapo]

Thanks Jim !

Maybe your'e right about Starline, I'll give them a try !

 

[FCoelho]

Be very careful when loading the Starline .356 TSW brass. It is not as strong as Federal brass. When Triton was doing load development with that cartridge we found out very quickly the differences between the two during pressure testing. We ended up loading all of the Starline stuff to mild levels for one of the members of our shooting team to burn through during practice. If you want full house power stick with once fired Federal brass.

 

[GooseGestapo]

FCoehlo:
Thanks for the heads up re: Starline brass.
I've had similar issues with Starline .40 S&W brass. Had several case head blow outs with Glock m22 until I discovered it was only with the Starline's. Not bad brass, just thicker and softer.
Any suggested loads for .356 TSW ?
Particularily the "lighter" practice loads.

 

[FCoelho]

I wish I could help you with loads but we only used OEM powders when we did our testing. They don't have an off-the-shelf equivalent that I can cross-reference. Right before we stopped testing I started playing with BE-84FS, which is a close match to Power Pistol, but that was for full house loads and they are not close enough for me to safely pass along the data.

From what I saw from our testing, VV N320, VV N330, and even Power Pistol can be used for a mild load. I would try using mid-range 9mm data and go from there. Hope that helps.

For what it's worth (not starting a cartridge war) we were able to exceed the performance level of 357 SIG with less pressure when we played with the .356 TSW. That is when using Federal brass.

 

[GooseGestapo]

Again, Thanks!
I'm probably not going to fool with that barrel for awhile, but it was good to find out all I need is some different brass. I don't know if .356 TSW Federal brass is even available any more.

Haven't heard of BE-84fs or BE-85 referenced in a LONG time!
You're probably right about the velocity/pressure of the .356 TSW as I've played with the .38 Super/ 9x23 a little.