.357 load too hot?

[Whiskey_Sour]

I was loading a mid range load of HS-6 with Zero 125 gr. Jhp and Remington small pistol primers. All was good until I changed to Winchester small pistol magnum primers. I noticed the Winchester magnum primers were flattened. Is this load now too hot? S&W 627 PRO, 9.8 GR. HS-6 mixed brass. No problems with extraction, or unusual recoil. Thanks.

 

[rcmodel]

It's probably just the primer is softer.

Your 9.8 grain HS-6 load is the Starting load according to Hodgdon data, so it is very unlikely you have excess pressure.

rc

 

[moxie]

Flattened primers in .357 loads are not unusual IMO.

 

[rcmodel]

You might look again.
125 XTP and 9.8 HS-6 is the starting load.

From Hodgdon site and my Hodgdon manual:
Start = 9.8 1,493 34,400 CUP
MAX = 10.9 1,629 42,100 CUP

rc

 

[moxie]

My electrons are faster than yours. Correction was already made.

 

[gamestalker]

When you switched primers, it probably changed the pressure curve to some degree. It's not that your load is too hot now, just the rate of pressure climb is now different. If the flattened primers bother you just switch back to standard primers.

 

[GLOOB]

Lots of people have noticed the current Win primers flatten more than other brands. The cups are soft, is all.

 

[Whiskey_Sour]

Thanks for the replies, I was thinking hard about pulling 150 bullets :banghead:

 

[ArchAngelCD]

It's been my experience Winchester primers seem to flatten easier than other primers. Add to that, like said above, flat primers are not all that uncommon in the .357 Magnum. Flat primers are not a good pressure gauge in handgun calibers.

 

[Whiskey_Sour]

Thanks, that helps put my mind to rest.

 

[Whiskey_Sour]

Well...decided to "bite the bullet" and buy a caliper. The loads that had no flat primers (Remington 1-1/2 small pistol) had a COL of 1.57, the loads with the Winchester magnum small pistol primers that flattened were COL 1.56. COL is supposed to be 1.59. Is this enough difference to worry about?

 

[kingmt]

No.

 

[ArchAngelCD]

Well...decided to "bite the bullet" and buy a caliper. The loads that had no flat primers (Remington 1-1/2 small pistol) had a COL of 1.57, the loads with the Winchester magnum small pistol primers that flattened were COL 1.56. COL is supposed to be 1.59. Is this enough difference to worry about?

You should crimp in the cannelure with revolver bullets. The OAL in the manual tells you where they crimped the bullet they used.

In a revolver round that long 1 100th of an inch means nothing...

 

[eldon519]

I shoot mainly Winchester SPM in my .357 loads, and even the magnum has a soft cup. Those things flatten if you just look at them funny, especially in Remington brass where the pocket mouth is a little more beveled.

 

[Whiskey_Sour]

Good, I had crimped at the cannelure, and have got it through my head that the WSPM primers flatten easily. Thank you very much for the feedback!

 

[loneviking]

Switch over to CCI primers, which are quite a bit harder. BTW, you'll know if you're getting a hot load with a .357 when you have to beat the shells out of the cylinder!

 

[Steve C]

Low pressure often mimics high pressure in regards to how flat the primers look so its quie possible that your start load low pressure is causing what you are seeing. Unless the primer is as "flat" as the picture below shows on the right it isn't really flat.

As long as the round goes off there's no reason to worry or chanage primers.


Note: This picture and link was borrowed from a post by RTMiller on 4/11/11.

 

[Whiskey_Sour]

Yeah, the primer on the right is more or less what they looked like, especially the Fiocchi brass. Like I said, there was no unusual recoil, and cases were not hard to extract. I did also shoot some factory Remington 125 gr jhp, and those REALLY DID get my attention On a side note, I ordered some X-Treme 158 gr copper plated SWCs. Anyone with a good starting load of those, HS-6, and WSPMs ?