Semi flattened primers, Normal in the 460 S&W Mag

Scrapper

Scrapper

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Moral of the thread. 460 S&W Magnum loads have enough pressure to semi flatten primers, So do not be too alarmed when you look at the primers on a spent case.

I lost my pictures so I edited the thread.
 
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Your replies will depend on the persons level of loading experiences BUT, IMO, while they are flat it doesn't appear to be anything excessive!
There's no cratering around the primer indentation so while they're a bit warm they aren't excessive. On a hot day i.e. 90+ they may be a bit of another story.
 
505Gibbs,

Thanks for input. It was 90 degrees that day, I'm glad you mentioned the "ambient temp. variations", it's very important.
 
they're fine, remember it is a 460......

when i shoot my 500 and the primers are not flattened, then i've got a problem;):D
 
Not owning a .460 myself, I'd run with the advice from the factory. They say OK, so be it.

FWIW, WLP cups are not as hard as CCI, which I understand to be the hardest.

I load a 260g GCTC from a mould designed by Casull and made by Lyman.

I load it at the upper edges of the Casull supplied data with the CCI SR primers as suggested. The primers haven't flattened so far - 20 years and counting.
 
Those are WLR's. Sorry I said WLP earlier. I just recently was able to get WLRM's so I will be trying those next.
 
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In the last pix shown, the angle is such that the primers don't even look flattened to me. I'd go with those any time. And, as 505Gibbs said above, there is no cratering. Cratering generally occurs at higher pressures and shows a slightly-raised and very sharp edges right along the edges of the primer. Occasionally, the primer will slightly flow back into the firing pin hole. The rule about high pressure signs is, though, "THERE AIN'T NO HARD AND FAST RULES." And sometimes there can be very high pressures with few signs to indicate this, although I've never personally seen this with my guns over the last fifty years.
 
I load the same brass and Starline uses Large Rifle primers not Large Pistol primers. Unless, you have found a very old batch.
Pistol primers are thinner and shorter than rifle primer and can fail to detonate in cases bored to depth for rifle primers.

WW296 is my favorite powder. It has a few quirks you need to keep in mind. WW 296 can be unpredictable at low loading densities. I start just below the mid loading range with new brass. Ball powder need a primer with strong brisience. Winchester primer were designed to light ball powders, other brands require a "magnum" primer. You must have a solid and firm bullet grip for consistent velocity spreads. That means trimming you brass precisely and having a taylored expander plug. I had Lee make me a factory crimp die $30 that does a better job with less time.

If you want a load with reduced power, use a different powder.
The great advantage of the 460 is three easily available power levels in three factory loadings. It is a great all around large pistol round. Good shooting.
 
I don't know why Hornady separates 296 and H-110 in their load data for the 460. The mfg says it's the same stuff. Anyway, I shoot 50.5 gr of either one with my 200 gr ftx's. with magnum primers

Your primers are not flat imo.
 
In my opinion none of those cases have "flat primers" indicating high pressure. I've seen a few flat primers in my day and your cases look normal for a 40K to 60K pressure round. If you look in the Lyman 49th edition reloading handbook they will show you examples of what an early stage of high pressure will do to the primer. If you look at the Lyman HP example and imagine that very thin pocket ridge totally disappearing - that's when you just proofed your cylinder and you won’t get away doing that very many times.
 
7P's,

Thanks for the reference you made there, I'm in the book as we speak to refresh my memory. I posted those pictures to strike up a discussion about what normal can look like and I'm glad I did cause I learned a few things myself from people who have dealing with higher pressure guns longer than I have.

Thanks Everyone for your comments.
 
Scrapper,

7Ps touched on this, but remember that the .460 operates in the same pressure range as most rifle cartridges, 50,000-60,000 psi. You need to be comparing primer appearance to a rifle cartridge rather than what a primer fired in a standard revolver cartridge in the 12,000-45,000 psi range would look like.

This is just like you can't directly compare a .38 Special to a .357 Magnum and expect to see the same thing.

If I saw primers that looked like yours in a full power .357, .41, or .44 Magnum I would not be a bit concerned as they appear completely normal in that application.
 
Alk8944 , Thanks, I do realize the pressure range in the 460 caliber, I would never compare this next to a lower pressure caliber, sorry if I made you think this.

Thanks again for your comment, I do read them all. :)
 
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