I load to the magazine limit. My rifle seems to be accurate enough without adding another troublesome variable like ammo of 2 diff lengths.
I believe the throating differential you are seeing to be pretty common. I have seen it in a Colt & a Rem 700.
On some hunts I am tickled to have remembered my hankie, knife & some bullets.

Imagine your grave on a windy winter night. You've been dead for 70 years.
It's been 50 since a visitor last paused at your tombstone.....
Now explain why you're in a pissy mood today.