Q-NL vs NL-Q

Did a little research on this topic but couldn't find an answer. I'm sure this is talked about in the CC newsletter but I'm not a member yet. But anyways here it goes:

Is there a difference between NL-Q or Q-NL markings? Or even H.I. or HI markings.

I know they were parts made by National Lock Co. and Hemphill Co. but does the order or type of marking have any meaning. For example was the NL-Q marking used for a specific Quality Hardware serial block while the the Q-NL marking was used for another block or were they both used interchangeably? Same with the Hemphill markings?

Just the way they were marked.

Q-NL was early use. By researching known originals, you can tell which part was used in a serial number range and then you can date a particular weapon.

Loren