2400 and the 357 Mag

[Peter M. Eick]

I was shooting 12.0 grns of 2400 on a 158 grn hard cast lead RN with a Winchester magnum primer and Starline brass. I had a "moderate" crimp, meaning that I had rolled the brass over the crimp groove but the brass was not completely seated on the bullet. I could go deeper on the crimp and noticed I was getting some unburned powder on my hands. Not a lot but more then I expected.

2400 is a new powder to me, so my interpretation is that I probably need a bit more crimp. A "heavy" crimp. Does this seem reasonable to you all?

It was a nice accurate mild load though!

 

[Old Pa]

That's the light end for 2400 in the .357; you may not be getting enough pressure for full ignition between "moderate" crimp and light end of powder charge.

 

[Peter M. Eick]

That was kind of what I was thinking. Thanks for a bit of confirmation.

 

[Quantrill]

I agree. The original Keith load was 13.5gr/2400 under a 168/173gr Keith SWC in .38 spec. cases. The load with the same bullet in the .357mag. case was 14.5 gr. I have cut back to 12.5gr/2400 for the .38spec and 13.5gr for the .357mag case and have had great results. The guns for the .38spec were heavy "N" frame guns only.
Quantrill

 

[critter]

2400 usually works best with heavy bullets, heavy crimps and top-end loads. Only then will it burn clean-and that seems also to be where best accuracy often is found. Good luck.

 

[EchoSixMike]

I run 14.0gn 2400 with the 173gn Lyman Keith and it works great in my S&W 686+. I also use the RCBS 150 Keith style SWC with the same load. They are cast at 155gn from wheelweights, water quenched at 450F. They run lower pressure than the Lyman bullets. I'm burning what's left of an older 20lb keg of 2400 and the story goes that new 2400 is faster, so don't go right to that 14.5gn load with new 2400. S/F...Ken M

PS: This is all in 357Mag cases

 

[JackM]

There's a thread on the Beartooth forum about this. Ed Harris posted his pressure data on page 2, and it's an eye opener. I've found that the 2400 and WSPM combination goes from mild to wild with a very small increase in the powder charge, and no longer use that combination.
http://www.beartoothweb.com/~forum/showthread.php?s=&threadid=5133

Bye
Jack

 

[Quantrill]

JackM,
Very good thread that you recommended.
http://www.beartoothweb.com/~forum/...=&threadid=5133

 

[moxie]

I've used 2400 in the ~18 gr. range with 125 JHP with outstanding results. I'd describe the crimp as firm. Very accurate. My favorite .357 Mag load.

The load you describe appears to be very light for 2400. I'd use Unique if I wanted a mild load like that. I save 2400 for fairly hot loads.

 

[JohnK]

I agree. The original Keith load was 13.5gr/2400 under a 168/173gr Keith SWC. I have cut back to 13gr/2400 and have had great results. Quantrill

Remember this was also using 38 Special cases because Keiths bullet didn't fit in the original 357 using magnum length brass. That is also covered in the thread Jack posted.

 

[JackM]

Let's keep this straight. Please state if any data you're posting is for .357 Magnum cases or .38 Special cases. As John pointed out, the original Keith loads were for .38 Special cases, and today's 2400 is not Keith's 2400, as Ed Harris discusses. If I remember correctly, Keith developed these loads for the S&W .38-.44 N-frames before the .357 was introduced.

Bye
Jack

 

[Peter M. Eick]

I am using new starline 357 mag cases.


And thanks for all the help.

 

[Pumpkinheaver]

In my experience you need a good firm crimp with 2400.

 

[mec]

A combination that works with 2400/ 357 and lead bullets of traditional weight is 158 grain bullet with the base touching the powder column with the bullet seated to the crimp groove. This generally amounts to 14 grains and performs differently with different bullets.

for instance, a machine cast 158 swc will do 1400 out of my 6" gp 100 and 1335 from the 4". Velocity is very consistent with CCI 500 STANDARD Primers- magnums not being needed with a 100% density load. My results with Winchester Western Magnum primers have been erratic.

14 Grains with the old lyman / Keith hollow point have produced the same small overall spreads - 50 fps - but velocities are considerably reduced because the overall bearing surface of the bullet is shorter. ( the front band on the lyman bullet is reduced in diameter

These are in .3576 cases and it is important to note that current handbooks have gone to reduced pressures. Loads of under 13 grains are generally deemed maximum and are not nearly as consistent as the older standard 14 grain charge.

 

[Gewehr98]

2400 is a fun powder with 158gr bullets!

My 6" .357 Desert Eagle was balky at loads that didn't generate optimum gas pressure. Alliant 2400 fixed that problem rather quickly, it's a pretty full case once the bullet gets seated, but accuracy and cycling are just fine.

 

[MCNETT]

I agree that you will need a firm crimp with any slow powder from a revolver, including 2400. 15.0gr under a 158 hardcast is an excellent load. Also, I have loaded 19.0gr under a 125 GDHP and 21.0gr under a 110JHP for a lot of flash and fun from my 4"GP-100! BTW, these loads are straight from Speer loading manual #11.
-Mike