Chambering Issue When Neck Sizing Lapua Rem 260 Cases

[HodgdonExtreme]

The fired case should be larger then the loaded round measurement so the case neck can properly release the bullet.

...Or at least the *same* diameter. There is a bit of springback, so if the fired caseneck measures, say, .2920", the chamber's dimension is likely .293 or .2935".

Regardless, I'm in agreement that it's wrong to be firing .293" (loaded diameter) ammo in a chamber whose brass comes out at .292". Especially for a field rifle.

I suspect that is not the OP's only problem, however.