I have a 1916, Winchester built P14.
I slugged the barrel and it is at .3135"
I thought that it might not like the smaller diameter bullets, but I was wrong.
The best shooting bullet in it is the Sierra 180 grain FB Game King. [.311"]
Another one that surprised me was the 180 RNSP Remington Cor-Lokt [.3105"]
But it actually shoots many bullets well, including the larger diameter Hornadys.
It is not unusual for this rifle to flirt with 1¼moa with loads I build for it.
One good thing....it is easy on brass, unlike the LE rifles.
Regards, Eagleye.