but I trust it more with a magnum primer on board.
Good advice, I've always felt better using mag primers with ball powder in cooler temps.
He mentioned it was a Winchester primer. The WLR is pretty strong among standard primers.
The mechanical issue made this moot anyway.
I don't particularly care for WLR primers after a go-round with them in my Garand. They kept popping at the radius and didn't do my bolt-face any good.
That's a load only running 42 Kpsi, I wouldn't want to light up a 58.5 Kpsi load and admire the divot.