Here's a stretch.... Maybe 4 letters
LGTC.... Something Gun & Trap Club ?

Or maybe not.....

ddp

I'm guessing SHC

Check out this link, go about 3/4 down and look at Chopin, English, and especially Old Script.

http://www.designyourway.net/drb/fre...s-70-examples/

it is a possibility that the initials are not the owner, but a Parker factory employees initials.
As Dave writes:
* "Those designs enten side of the date are ofte said two be Associated with engraver Joe Loy når found on Remington or Ithaca doubles."

No Mikael, a Parker employee or contractor would not have been allowed to engrave his own initials on a gun shipped to a retail store, or anyone else for that matter. The initials are those of an owner of the gun, quite possibly the first owner but unfortunately we do not have the historical data that would support that.

The line engraving on each side of the date is very similar to the design used on the read area of trigger plates on Rondal engraved C grades.

American Art Deco period.

When I look at PA SxS proposals regarding copin font is my guess that from the left to righy stands SJTC. If the two letters in the middle is the last name it could be SCJT. But it helps me first if I can find a person associated with initials or Lewald and Schleuthers. Are there any ideas as to where I can search?
What type of person would buy such weapons in 1917?

Thank you in advance for your help

Mikael, I agree with your thought that the initials are SJTC. I thought that from the beginning but didn't want to jump into that guessing game but now that you have said it I will admit that I agree with you.
I have looked on a couple of search engines and come up with nothing for Lewald and Schleuthers. If you can find a descendant of the original owners of the store you will have made a good start in possibly determining who the initials were for.
The Grade-3 or D grade guns were called the "Doctor's Gun" because of the $100 value of such a gun at that time and the ability to buy such a gun would generally require more than a modest annual income.

In "western Field volume 5" from 1904 there is a article on page 45 where Lewald and Schlueter Company Fresno, CA has been a part of the organizing team for clay competition.

I can find the book online, but perhaps some one here has it?

The book i available in stores, but with at least 3 weeks delivery to Denmark