H110, 357's, and flat-ish primers.......

CanadianNorth

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Ok,

I have been working with HS-6 and Winchester 125gn hollow points for a while. I load them up around 90-95% (that works out to about 10-10.5 gns of HS-6 for me) and they shoot pretty nice, not quite as powerful as factory loads, but the paper targets and the tin cans can't tell the difference.

Having read about the high velocities w/H110 I thought I would give it a go.
So, I tried some on them this past weekend with a 97% load (21.3 gn) <<not sure why they say to only go 3% down on H110, but anyway...>>.

They loads seemed fine, 'bang', kick (not much kick in my Winnie '94 Wrangler), and muzzle flash were pretty much comparable with factory ammo.
But, I did notice a little flattening on the primers with this ammo.
I put in a pic so you can see.


So, the question is simply this - Is this something I should worry about? or a non-issue?

Thanks.

P.S. The top casing is the 97% H110, the bottom-left is 90% HS-6, and the bottom right (silver primer) is the factory load.

357_1.jpg


357_2.jpg
 
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I have the Twenty Fifth Edition Hodgdon Manual, printed 1990.

For a .357, small pistol magnum primer, 125 grain rifle load using H110 it suggests a starting load of 18.5 and a max of 19.0.
 
Perhaps I missed it, but did not see what primer you are using. Primers of different brands have differing thicknesses of the cup. This alone could account for your 'flattening'. See James Calhoons article on PRIMERS AND PRESSURE ... Its not geared toward .357, but may help you somewhat.

http://www.jamescalhoon.com/primers_and_pressure.php

FWIW I don't think you have a problem, but you should get a good manual with pressure information (LEE) if it worries you.
 
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There's not any significant flattening here: all the primers' edges are still radiused and I don't see evidence of high pressure. Did your rounds stick upon extraction?
Usually, H-110 gets better velocity at a lower pressure than most powders, the trick being its longer than usual pressure curve.
PP.
 
no, no prob with extraction.

I had figured that the flattening was minimal, particularly because I was under the max on the load, but I wanted to be sure.

- - -

Here is a question you may be able answer,

why can't u use rifle powders with rounds like 357/44 in a rifle?
I would suspect that using a slower powder in such an instance might be ok, given the longer barrel/burn time??

<:eek: < no, I am NOT about to try this, nor would I even if some out there said 'go for it'. I don't even use max loads, let alone mess with anything like this>:eek: >
 
It has to do with bore to case size ratio....slower burning "rifle" powders will disappoint in handgun cartridges....you'll get: lower vel., inconsistant vel./ignition, lots of unburnt powder.
 
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