FY 07-08 production at Frankford, Part II, Class IV, Section 5 lists a "Body Gauge" for the 1906 cartridges. They made one:
(You need to Login to view media files and links)Note the "price" was $4.90 but we'll get to that.
FY 08-09, same section, doesn't list any:
(You need to Login to view media files and links)Pamphlet 1879, Price list of Ordnance Stores, dated 1914, page 69, lists the body gauges for 1898 and 1906 cartridges at $2.35. They're absent from the 1917 edition (which will eventually become a wallpaper panel....).
(You need to Login to view media files and links)Body gauge for the 1898 cartridge.
(You need to Login to view media files and links)Made at Frankford in 1908. It doesn't show up in their production reports.
Interesting mystery.