Did Hodgdon data include pressures over SAAMI spec ? (answer = NO)

[Strat Rider]

I will be picking up a .357 Magnum soon so I started to look at the reloading data on Hodgdon.
Research indicates SAMMI spec has a max 35,000 pressure for this caliber but Hodgdon also provides data for 57 max loads and even 12 starting loads that exceed SAMMI specs.

I am trying to confirm or rebutt a single item I read along the way that SAAMI lowered pressures for the 357 Mag by roughly 25% due to evidence that psi over 35,000 was causing eventual damage to revolvers (usually double action) but these higher pressures are still safe else Hodgdon would not publish them.

Please comment on this observation as it truly has me wondering why Hodgdon would provide possibly dangerous load data.
My personal thought is perhaps it's okay to load higher for single action revolvers or rifles. Your Thoughts?

 

[Rule3]

What bullet weight are you looking at. Sure you are not looking at CUP??

 

[.38 Special]

The change was made - in more than just the .357 - due to a general changeover from the copper crush method of testing to electronic (piezo) PSI testing. It turns out that copper crush testing can underestimate peak pressures by quite a bit - apparently duration of pressure can produce misleading results with the method - and so with the advent of piezo testing, many loads were reduced by about 20%.

I strongly suspect, as @Rule3 points out, that the issue is not Hodgdon publishing dangerous recipes, but rather some confusion about units of measure.

<edit> After looking through all of the loads listed at the Hodgdon "Reloading Data Center" I see that some loads are shown with CUP measurements and some with PSI measurements. It may simply be that they do not have piezo testing data for every single load. Regardless, I'd bet serious money against Hodgdon publishing dangerous loads.

 

[Metal God]

Yeah what bullet are you referencing and or powder . I just checked 158gr and 125gr two of the most common weights with H110, cfe , HS6 & 700x , none go over 35k psi . In fact none even come close .

 

[.38 Special]

Yeah what bullet are you referencing and or powder . I just checked 158gr and 125gr two of the most common weights with H110, cfe , HS6 & 700x , none go over 35k psi . In fact none even come close .

If you select "all bullets" and "all Hodgdon powders" for the .357 you get 133 loads, some of which exceed 40,000 CUP. I'm betting that's what threw the OP for a loop.

 

[Otto]

Maximum pressure is 35,000 PSI and 45,000 CUP. Hodgdon uses one or the other depending on the load.

 

[Strat Rider]

You folks are absolutely correct - everything exceeding 35K were all measured in CUP not psi.
I always use "Select All" for bullet weights and powders then transfer all of it to a spreadsheet for sorting and overlooked the CUP.
Jeez, I love this forum for pointing out things that I sometimes miss or overlook.
Based on this - I will now assume that even the max pressure of 43,200 CUP is still within SAAMI spec. of 35K psi. Even though the conversion table I used would indicate 43,200 cup = 47,589 psi. Can't trust any conversion.

What bullet weight are you looking at. Sure you are not looking at CUP??

If you select "all bullets" and "all Hodgdon powders" for the .357 you get 133 loads, some of which exceed 40,000 CUP. I'm betting that's what threw the OP for a loop.

 

[higgite]

SAAMI max CUP for 357 Magnum is 45,000.
https://saami.org/wp-content/upload...FP-and-R-Approved-2015-12-14-Posting-Copy.pdf
Page 11

Mods: Can someone reword the title of this thread because it's not true. Or maybe just delete the thread since it's based on misinformation?
Edit: Nevermind. OP fixed it. We're all good.

 

[.38 Special]

SAAMI max CUP for 357 Magnum is 45,000.
https://saami.org/wp-content/upload...FP-and-R-Approved-2015-12-14-Posting-Copy.pdf
Page 11

Mods: Can someone reword the title of this thread because it's not true. Or maybe just delete the thread since it's based on misinformation?

That's a bit harsh. It seems to have been an honest mistake. I have been reloading for decades and had never noticed that little tidbit from Hodgdon, and now I know a little more than I did when I woke up this morning.

 

[Cliff6]

.....well, the title isn't fair to Hodgdon Powders. The information is useful to read, just the title isn't fair now.

 

[.38 Special]

.....well, the title isn't fair to Hodgdon Powders. The information is useful to read, just the title isn't fair now.

Yes, I see your point.

 

[Strat Rider]

Fixed it myself - that was a good observation.

Mods: Can someone reword the title of this thread because it's not true. Or maybe just delete the thread since it's based on misinformation?