Very good question. I've got some old ones that are large pistol primers. I just have them on display.
The Winchester box I was told might be okay but to test for misfires before loading a complete cartridge.
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Now the Remington primers I have. Well the box l have looks sketchy by it's condition so I'm not sure. Water damage/humidity.
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We have one gentleman here that, besides a reloader, happens to be a retired explosive ordnance professional. So he may have more insight into this.