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Clark Howard
11-16-2018, 04:30
I have been reloading rifle and pistol cartridges for many years, but up until now, (Thanks Unique and 4895), I have never used a powder or load that specified a magnum primer. My question is: What problems or complications will I encounter using regular small pistol primers to load a mid-level 357 cartridge for use in a Ruger single action and a Winchester 1892 carbine? Thanks for any input. Regards, Clark

Sunray
11-17-2018, 09:33
The only thing that might happen using magnum primers is an increase in pressures. However, the primer has nothing whatever to do with the cartridge name. They're about the powder used only. Neither Unique nor IMR or H 4895 require any primer other than regular primers. Despite what Hodgdon used according to their site. For reasons known only to them they used a magnum primer with magnum named cartridges but not with non-magnum named cartridges with the same powders. You'll note their rifle and handgun .357 data is the same too.
Magnum primers do aid ignition in extreme cold though. No set temperatures where it absolutely matters, naturally.
The only other thing that'll crop up when trying to use the same ammo in 2 firearms is that accuracy will not be the same out of both. You might get lucky, but it's unlikely. You really need to work up a load for each. It's not unsafe. Just an accuracy thing.

Clark Howard
11-17-2018, 12:15
Thanks for the guidance. I don't plan on using the same load for carbine and revolver. You are correct, Hodgdon does seem to call for magnum primers in "magnum cartridges. My plan is to work up a moderate velocity 158 gr hollow point load for the carbine, and a lower velocity soft point load for the revolver. Thanks again for the help. Regards, Clark

Major Tom
11-18-2018, 02:37
Used magnum primers in all my calibers. No problems.

Sunray
11-18-2018, 09:17
"...Hodgdon does..." It's almost like one of their clerks or maybe their web site guy did it. They do the same thing with H110. Magnum primer for .357 loads, but not for .30 Carbine. IMR4227 works better in .30 Carbine anyway.

Allen
11-18-2018, 12:41
I once loaded a handful of 357's using H110 powder. The Speer manual clearly states that magnum primers are required for this load/powder. Somehow I missed it and used standard small CCI pistol primers. Using a S&W model 28 6" barrel a couple of rounds shot well, the rest of them had a reduced report and the barrel and chambers were full of unburned powder. If these had been shot with a rifle the bullet may not have exited the barrel.