All About Pocket Knives

I recently got this knife. It appears to be a #33. A tipped blade but otherwise ok- too bad they didn't invent phillips screws sooner, that might have kept alot of guys from using their pocket knives for screw drivers.
anyway... it has steel liners and a 4 line stamp. There are no periods in the U S A part of the stamp. The USMC 4 line has no periods, but this does not look like that stamp. Is there any significance to no periods or am I being too nit pickey? Also when did Camillus start stamping model numbers on the knives? And is it a reliable method to date Camillus knives?

Trying last night to answer the above questions on my own, but ended up with another question. I looked at several #33s, the op knife is the only one I saw with a bail (called a 'shackle' by Camillus). Is my knife really a #33? There is no model number on it. Thanks
Bruce

Not too sure about the periods, never really paid any attention, however, very few Camillus knives produced before WWII were pattern stamped (out of about 200 Camillus knives I own, 7 pre-WWII knives have pattern numbers and all of them are 4 digits).

After the war many Camillus knives were patten stamped, usually with a 2 digit pattern number.

Your knife was produced pre-WWII (or perhaps during) and would probably have had the pattern number 2033 if it had been marked.

JMO

Berryb, check this out: http://www.collectors-of-camillus.us/ In the section Camillus knives of WWII there is a drawing, an EZ open with a bail/shackle. The military number appears to be 5541/2. It looks like a #33 except for the bail. Didn't notice dimensions.
Treefarmer