Dating a System #X Peterson pipe

[paulie]

The hypothetical subject of this exercise is a Peterson pipe I'd like to date. In the absence of COM markings and with faux hallmarks, the only markings left are Peterson System #x, say System 4 or System 3. Pipedia and the Peterson dating guide do not explicitly state that those system designations were only used in the pre-republic period, but the only references I could find for them were confirmed pre-republic pipes. Are they enough by themselves to confirm pre-republic dating?
Discuss.
No, seriously, input from Peterson connoisseurs would be most welcome.

 

[ssjones]

I don't believe it is possible to date with any accuracy a Peterson lacking hallmarks or the COM.

 

[ssjones]

Even only briar nomenclature is not an exact science with Peterson.

 

[rblood]

Al is absolutely right, dating a Peterson to a particular year without a silver mount can be near impossible. Without hallmarks you can get clues as to date ranges by using COM styles / text (if there is one) and what type of font style is used in various stampings, shape numbers, etc.
As a general rule (and to answer your question) the grading numbers are seen from around 1920's through the end of the 1940's I believe, so yes there is a high likely hood that a pipe with a grade number is pre-republic - exact science? Umm, no, not with a Peterson. You see the grading numbers both inside a circle and sometimes on their own without the circle. While I would not bet on it, my feeling is the number in a circle is the older of the two styles.
For what it's worth, COM stamps were rare prior to 1920, but you sometimes see pipes without a COM right up to present day - call it factory errors or whatever, it's just another Peterson quirk.

 

[rblood]

Also note that those grading numbers also appeared on patent pipes as well, but those certainly would be identifiable as patent era, not pre-republic era pipes.

 

[paulie]

Thank you all very much for your answers. I should've been more precise with my question. While finding out a year range as precisely as possible is interesting, I'm most interested simply in establishing whether such pipes are pre-republic. My takeaway from your comments is that (barring some mishap at the factory) they are.
On a sidenote, do any of the commemorative pipes made in the modern era emulating pre-republic pipes ever have the same style of COM markings, eg block/circle Made in Ireland?
-p