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View Full Version : 44 Magnum Flat Primer Concerns



Hawker man
11-26-2011, 12:25 PM
I have been loading a light 44 mag load, 6.0 grains of Tight Group under a 240 grain Hard Cast SWC, to shoot out of a 629 for targets. No problems, happy with the powder puff load, accurate, easy shooting load. I can shoot them all day long.

I purchased a Ruger Super Blackhawk Hunter and figured I try my hand at some more peppy loads. I got some Alliant 2400 and found the load data at; http://www.reloadammo.com/ He says 20.6 grains max, start at 10% lower 18.5 grains. Being the cautious type I figured I'd start at 17.0 then 17.5 grains. I'm using WW Super brass, PMC large pistol primers, 240 Grain SWC Hard Cast bullet with what I would call a firm crimp. With the 17 grain load I noticed some unburned powder and did not notice any unburned powder with the 17.5 grain load. Groups were acceptable.
My concern is with the flattening of the primers on the fired shells. I'm worried about moving up through 18, 19 then on the the 20 grain powder range.

Questions
1. Do these primers look to be excessively flattened for a load that light?
2. Am I causing extra pressure by starting below the recommended minimum?

http://i451.photobucket.com/albums/qq238/HawkermanZ/2400-170.jpg

http://i451.photobucket.com/albums/qq238/HawkermanZ/2400-175.jpg

leadman
11-26-2011, 12:36 PM
Those primers look fine. There is a slight flattening of the center, but the edges are still nicely rounded of the 17gr cases. The 17.5 gr show normal flattening but are still fine.

I shoot 18.5grs with the Lyman 250gr "Keith" boolit in my 44mag SBH. Good load.

If you deprime the cases and look at the primers you will see the edges are still rounded.

mdi
11-26-2011, 01:38 PM
Usually when primers are flattened by pressure, they are flush with little or no radius on the edge; flush with the case head. On some light loads the case won't grip the cylinder walls and slide back and hit the recoil shield and slightly flattening them. I use case extraction and measuring the case just above the rim when watching for high pressure in my revolver loads...

GRUMPA
11-26-2011, 01:45 PM
They (the primers) really don't look all that flat to me and to honest some of mine look flatter than yours. But when I push the envelope on power I also check the power ring diameter when doing it also.

geargnasher
11-26-2011, 02:07 PM
I've fired many pounds of Keith SWCs powered by 19.5 grains of 2400 (seemed to give the best accuracy average, but I was using a totally different alloy) with nary an issue.

Compare the primers of your reloads to the primers of factory copper-jacketed ammo, you'll note a big difference in pressure there with the factory stuff being much flatter than what's in your pics. Your loads are still quite mild by .44 Magnum standards.

One other thing that can flatten primers terribly and has nothing to do with excessive pressure is headspace. If the rims of your particular batch of cases are thin, or if the tolerance between the recoil shield and the rim recess in the cylinder is excessive, the primer can back out of the case slighly until it hits the recoil shield when it first pops, then as the pressure of the burning powder builds, it pushes the case head back against the recoil sheild, too, but has to reseat the primer under pressure to do so. The primer ballons, mushrooms, and is hammered flat back into the pocket, creating an almost invisible line between the primer and pocket. Just something to be aware of for future reference.

Gear

williamwaco
11-26-2011, 02:07 PM
Questions
1. Do these primers look to be excessively flattened for a load that light?
2. Am I causing extra pressure by starting below the recommended minimum?




2: No.

1: Those primers are not "flattened primers"
Actually the one on the left looks rather mild.


This is a "flattened primer...



37893



This is not by any means an extreem example. They occasionally get even flatter than this. Sooner or later you will see this by accident. Do not attempt to do it on purpose. This is not a sign of "High pressure" or "maximum loads" it is a sign that you have already gone too far.



.

shovel80
11-26-2011, 07:09 PM
No..yours are not bad...When they are...they start to fill out the WHOLE Primmer pocket!!
Like Willianwaco's photo...they are deffinately too HOT!

Terry

shovel80
11-26-2011, 07:13 PM
Years ago in the 80's....My Old Hunting partner used to shoot a Ruger Black Hawk .44Mag. with 24 Gr. of 2400 and a 240 Gr. Keith Bullet...Those were HOT...I shot mine a little milder!..
I wouldn't go beyond today's Loads...!...Don't try the 24 GRs...!!..

Terry....

303Guy
11-26-2011, 08:16 PM
http://castboolits.gunloads.com/attachment.php?attachmentid=37893

Mmmm .... I'm not sure that's actually a 'flattened' primer. I don't look at the edge so much as the firing pin indentation. I don't see too much 'squaring' of the indentation. That primer looks like mine when I haven't fire-formed a case i.e. primer back-out. Not holy writ by any means. williamwaco is in better position to judge as he has the gun and fired cases in his hands plus he is able compare them with other loads.

HollowPoint
11-26-2011, 08:24 PM
Just recently I noticed that the primers I've been using looked very much like those in your pics. I kind of wondered the same thing.

The primers in questions were Winchester LR magnum primers. I was using them to ignite 16.8 grains of 2400 loaded in a 7.5x55 cartridge for my K31 and they do tend to look flatter after being shot than the CCI primers I've use as well.

I'm just assuming that the metal used to make the Winchester primers may be a little softer than the Nickel-Plated primers from CCI.

I haven't had any problems with either one; I just noticed that one always looks flatter than the other after firing.

HollowPoint

MtGun44
11-26-2011, 09:14 PM
They all look OK to me.

A truly flattened primer will have a ridge around the top edge when you take it out, this is
where it flowed into the radius on the top edge of the primer pocket. Those show about
max loads.

Bill

Hawker man
11-26-2011, 10:25 PM
All:
Thanks for the answers, I'll be moving on to 18 grains then up by .2 at a time to about 19.

44man
11-27-2011, 09:42 AM
What Gear said!
Those are no where near flat and look like moderate loads. My primers with my heavy boolits look like that but if I go to 24 gr of 296 with a 240 gr XTP, they do flatten a lot more but since primers are a very poor indicator of pressures, my brass has lasted for over 40 reloads. I ignore primers. I know my loads are safe and since I use the Fed 150 with a softer cup for all .44 loads, they can go ahead and get flat.