9x19 , HS-7, Speer #12 load data to HOT?

[243_shooter]

Hi guys,

You all were spot on with the last advice you gave me, now this newbie has another question..

I loaded up some 9mm 124gr FMJ RN per the data in speer #12, 8.0 gr HS-7 (starting load).. It's the only listing I could find for 9mm w/ HS-7..

They have max listed @ 8.9..

This was with an OAL of 1.135..

I'll admit to being a complete newbie to realoading, but these babies seemed HOT.. Made factory 124gr gold dot's seem like 22's..

Only shot 2, decided something was seriously not right, checked the brass.. cases look fine (once fired speer +P nickle).. but the primers expanded completely to fill the primer pockets (I guess you'd call this a flattened primer?)..

Got home pulled two of the loads down, 8.0 gr's spot on..

Would I be wise to try a lighter load, or just forget about loading HS-7 in 9mm? I've got 3lbs and would like to shoot it up. I was thinking about reducing the minimum load data 10% and trying again?

Thanks for any advice.

Leo

 

[PaulS]

243_shooter,
If the "flattened primers" show a raised ring around the firing pin dent then you might have too much pressure. (you might also be using an other primer than the CCI that is listed for the load)

A note here about primers and light loads: If your load is light enough that the cartridge is pushed forward by the hammer fall and the pressure pushes the primer back out of its pocket a bit before the pressure can expand the case to the wall of the chamber - before it gets a chance to seal against the chamber the case can be driven back against the breech of the gun and flatten the primer. Showing a "flattened" primer but no signs of excessive pressure.
I have personally found that some of the loads listed in the Speer manual are too hot for MY weapons even in a 357 Maximum TC Contender. I do not, therefore, rule out the possibility of excessive pressure but I would take the load up .2 (2/10) of a grain and reshoot. If things get worse then back it down to 7.8 and try that. If you get flattened primers with all the loads then use that powder for other cartridges and find another for the 9mm.

PaulS

 

[Steyr Hahn]

HS-7 From 5.6 grains to 8.9 grains
9x19mm Luger loads @ Stevens Pages. Com

 

[243_shooter]

Thanks for the info guys..

Paul, this thing was kicking like a MULE.. Typically the brass lands aobut 6 feet to my right in a nice pile.. The two hotties were another 4 feet past that!

Steyr, thanks for the link that's a great site..

I'm going to try backing the load down and see how they do.. I'm not concerned with max velocity I just want a decent plinking load to use up all this powder

I wish I had started reloading about 15 years ago, this is just way to much fun!

Leo

 

[grenadier]

What brand of primers were you using?

I've used 8.2 grains of HS-7 in combination with a 124 grain Speer Gold Dot, COAL = 1.125", with a CCI primer, and didn't see any flattening, but when I used this recipe with Federal primers, the softer primers would flatten.

 

[243_shooter]

They were winchester small pistol primers.. Maybe that's the cause?

Leo