Partial sizing is FL sizing. What it does is resize the case to fit the rifle chamber the case was fired in! There are min size and max size that work in rifle chamber's.Do a couple neck sizes with an FL die and you probably won't get it to chamber again. At that point start moving the sizing die down a bit at a time till the case will chamber easily. before that point you'll find you can chamber the case but you'll also feel a rub. That's from the shoulder not being pushed back quite enough And it's rubbing in the chamber, close but for me not close enough. Some guy's like to feel the shoulder rub!
