I found the following Turk Mauser info over on Gunboard's K98 forum, written by DocAV, a very knowledgable Mauser collector:
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For further detailed info, go to Parallax "Turkish Mauser Board"
Three (or four) basic groups of "Turkish Short rifles" post 1930s:
A. M1903/37 short rifle: a conversion of M1903 to the short rifle format,in 7,9mm, following some 1920s shortening of original 7,65 calibre M1903s to a 24 inch barrel: Marking "ASFA ANKARA" and 1937 date, similar to M1903/30 calibre conversions.
B. Kar98a refurbished, dated 1937: Just that new stock without all the bits of the original Kar98a; occasionally new barrel, stepped ( orig, kar barrel tapered)
C: Gew98/37 Short rifle: the title says it all; new stock, new barrel, ASFA Ankara marking and 1937 date. May also have 1938 date (different serial block.) Front band may be "H" band, rather than Turkish 93/03 band Sights may be "eared" (kar98a) or Standard.
D: "Kirikkale Short Rifle", Dates 1944-46, about 15,000 made. Same structural details as long "Kirikkale" Turk Mausers, except shorter barrel and "eared" front sights.
Other Turkish short rifles: During the immediate post WW I reconstruction period, many WW I rifles were "shortened" for Gendarmerie and Cavalry etc. Use: exampls seen include all the Turkish Mausers (M90, 93, 903

and the Gew88; Some were "short rifles" others, with side slings attached, were "Carbines". The variety seen on the web photos is enormous, as the work was carried out mostly by district Base workshops or divisional armourers during the Greco-Turkish war and the Civil War ( 1919-1923). Some are very professionally done.
Designators "M38" and "M38/46" are Importers invention, and should not be used, as they lead to misinterpretation as to what the rifle actually is.
The Turks themselves considered Every 7,9mm rifle as a "M938" irrespective of when it was introduced.
Hope this little dissertaition has helped our new collector.
Regards, Doc AV
AV Ballistics