the throats are typically cut as a specific angle…
Check that your bullet is passing smoothly through your OAL cartridge, sometimes they can hang up and cause that.
A throat is normally short or long / not undersized…
NORMALLY on a factory rifle the free-bore is cut with a standard reamer so all of them are over, or all of them are over (short vs. long)
I would check for burrs on everything, then I’d use a Sharpe market and color the tip of a bullet to see if / where I’m touching lands when shoving the bullet in to see if one of the lands (or all of them) are cutting into the bullet at that point vs. being seated harder.
