# Magnum Primers?



## leam (Sep 15, 2006)

Any reason to, or not to, use magnum primers for regular pistol target loads? My assumption, subject to facts, is that they would provide more fire to ensure everything got ignited at roughly the same time and you'd get more FPS out the muzzle with a given load. 

Leam


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## jfdavis58 (Jul 10, 2007)

I'm inclined to use what the loading manual tells me to use. I doubt that the increase in velocity would be noticeable. The thought of 'lighting all the power effectively' is also questionable. Once smokeless powder gets going, it goes pretty well; and it's supposed to burn not detonate!



leam said:


> Any reason to, or not to, use magnum primers for regular pistol target loads? My assumption, subject to facts, is that they would provide more fire to ensure everything got ignited at roughly the same time and you'd get more FPS out the muzzle with a given load.
> 
> Leam


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## mactex (Jan 23, 2007)

In addition to being a more agressive ignition source, a magnum primer will also raise the pressure in the case more than a standard primer. Depending on the load you a using, the magnum primer could raise the pressures above safe levels. 

If you decide to work with a magnum primer, besure to reduce the starting powder grains a bit to conpensate. That said, I can't personally think of any good reasons to do the substitution.


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## OMSBH44 (Jul 7, 2006)

*Reason to use magnum primers*

Winchester 296 powder.

It has been written several places that W296 powder requires magnum
primers for consistent ignition. It has also been written several places that
it is not a powder to be used in reduced power loads.

I found it to make very accurate full power silhouette loads in my 
.44 magnums. However, I also noticed a bit of gas-cutting of the top
straps in all the revolvers in which I used it.

So, I don't use it any more.

There may be other powders that are supposed to be hard to ignite that
may require the use of magnum primers. Like my father used to say: "If
all else fails, read the manual!"

L8'er, THP


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## Bob Wright (May 10, 2006)

I have used magnum primers with standard velocity loads with no ill effects. These were not anywhere near peak pressure, so any slight increase in pressure went un-noticed. I used CCI magnum primers in .38 Special and .45 Colt loads, also mid-range loads in .357 and .44 Magnums.

On the other hand, using standard primers with Winchester 296 in .45 Colt rounds did produce squib loads in very cold weather. The primer fired and compressed the powder into a "pellet" behind the bullet, pushing both up into the bore and lodging the bullet. The powder fell out as a pretty much intact pellet.

Both Remington and Winchester large pistol primers are dual purpose for magnum and standard loadings.

Bob Wright


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## Bob Wright (May 10, 2006)

OMSBH44 said:


> Winchester 296 powder.
> 
> It has been written several places that W296 powder requires magnum
> primers for consistent ignition. It has also been written several places that
> ...


OMSBH44,

I used the term "gas-cutting" in a post several years ago and was severly taken to task for it. It was not gas cutting, so the correspondent advised me, but particle abrasion that did the damage. He told of lubricating the top strap with graphite, or using a No. 2 lead pencil, to eliminate the cutting. He cited numerous attempts to recreate the "gas cutting" in testing without any results.

I'm still not convinced, though.

But, the worst case I experienced with cutting the top strap was in a .357 Magnum Blackhawk using ammunition loaded with Hercules (then) Unique powder.

Bob Wright

Bob Wright


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