Starline .500 S&W Mag


#1

I have two starline .500 S&W mag cases, but what is the meaning of the third star in the centre of the line on one of them. These are (obviously) both brass cases.

The headstamp of one is:

500 S&W MAG R

and the second is:

--* 500 S&W MAG

I presume the “R” on the first stands for “Revolver”, but what is the meaning of the extra star on the second?


#2

Falcon–The “R” stands for Rifle Size Primer. I have no idea about the extra “*”.


#3

Thanks. I thought all of these used Rifle Primers anyway due to the extremely high pressures generated by this round.


#4

Falcon

The very large caliber pistol and/or revolver ammunition is not loaded to “extremely high pressure”. Like all ammunition, it is loaded based on the strength of the particular firearm it’s intended to be used in. The reason for using pistol rather than rifle primers is because powder charges are lighter and the firing pin strike is generally less in handguns. The thinner cup thickness and cooler primer compound of pistol primers ensures positive ignition.

Ray


#5

Falcon–When Cor-Bon first started loading the .500 S&W Mag. they use Pistol primers. When they were found not to work well, they changed the size of the primer pocket to use the Rifle primers. Since, the primer pocket was the the wrong size for the pistol primer for reloading, they added the R to the headstamp so reloaders could tell the two cases apart.


#6

Ron

I believe that Starline always used the large sized primers. When they started experiencing pierced primers when using the large pistol primers they deepened the primer pockets an additional .006" to accomodate large rifle primers and the problem went away. Handloaders with the older brass can simply ream out the pockets with a special tool without compromising the case strength in any way.

Ray


#7

Ray–Thanks for the clarifcation. I knew the “R” stood for “Rifle Primer” not “Revolver”, but did not know exactly what the difference was in the primer pocket.


#8

Thanks, cleared that one up.