Ruger Mark IV Standard

THE PAGE MARKETS TWO MODELS. Model 40105 is the same Standard with a 6 in barrel, shown on the same page at the same price. It links its own spec sheet, but it is a separate listing under the base-model rule and none of 40104's figures may be carried to it. The wider Mark IV family (Target, Hunter, Competition, Tactical, the 22/45 and 22/45 Lite) are separate product keys entirely. RE-VERIFIED 2026-09-30, AND THREE THINGS CHANGED. (1) RUGER PUBLISHES METRIC. The per-model spec sheet (specSheets/40104.html) prints every length and the weight in both systems, so no value on this record is converted any more. Ruger truncates its metric: 9 in is 228.6 mm and is printed 22.8 cm; 4.75 in is 120.65 mm and is printed 12 cm. The centimetre figures are written here in millimetres, which is a decimal shift, not a conversion. The width row reads plain "Width" (1.20 in / 30 mm), not "Slide Width" as on the RXM and LCP MAX, so it stays recorded as overall width. (2) THE YEAR HAS A LAUNCH SOURCE. Ruger's release "Ruger Continues to Grow the Mark IV Line" (September 6, 2017) announces "two Mark IV Standard models" with 4.75 in and 6 in barrels. It agrees with 40104's own `introDate` of 2017-09-05, which the models page still embeds, so year introduced stays 2017 and is now footnoted to the release. The Mark IV line launched in 2016, as the 2017 release itself says ("Since the launch of the Mark IV in 2016"); the Standard models joined it in 2017, so 2017 is the Standard's year, not the line's. (3) THE WARRANTY IS RECORDED. The spec sheet's Instruction Manual link (dataProcess/manual/fetch.php/ms/40104/) resolves to the Mark IV manual, whose last page (PDF p. 48) says Ruger "has elected not to provide any written warranty, either 'limited' or 'full'". That is recorded as the warranty, the same as on the other Ruger records. THE SLIDE FINISH IS DELIBERATELY UNSET. Ruger's JSON carries both a firearm-level `finish` ("Blued") and a slide-specific `slide_finish`, which is empty here. Recording Blued as a slide finish would fill a slide-specific field from a firearm-level one, and this pistol has an internal cylindrical bolt rather than a slide, which the spec sheet describes. Ignition, trigger action and operating system are unset. Ruger's `action` field reads "Rimfire", which is a cartridge class. The manual never uses the words blowback, recoil-operated, striker-fired or hammer-fired, and its mentions of a hammer are parts and procedures ("This cocks the hammer", PDF p. 15), not a classification. NOTE ONE SUBSTRING TRAP THIS PAGE SETS: "hammer" in "cold hammer-forged barrel" is a manufacturing process. Height and weight carry basis notes because Ruger does not say whether either includes a magazine. Also published and unrecorded for want of a schema field: a 1:16 twist with 6 grooves, an alloy steel construction with an aluminium grip frame, checkered synthetic grips, a tapered barrel, a drilled and tapped receiver, UPC 7-36676-40104-8, the $579.00 suggested retail price, and Ruger's explicit discontinued flag, which reads 0.