G'day all.
I know what length of pull is, don't really know how I would pick it though if I had to be specific about it.
I bought my two Remington 700's without knowing anything about length of pull at the time.
By happy coincidence they fit me well and felt comfortable so I just got them.
What's the test for purposely choosing the right size though? If I got an adjustable or custom stock for a bench rifle or something like that in the future.