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400 COLT MAGNUM
400-COLT-MAGNUM-FULL
400-COLT-MAGNUM
IMPERIAL HANDGUN .40" UP TO .449"

400 COLT MAGNUM

400 · 1 headstamp · 1 scan
Calibre400
In the cabinetIMPERIAL HANDGUN .40" UP TO .449" · 2 images
Headstamp of 400 COLT MAGNUM
Reading the headstamp
12 o'clockMaker's name or factory code
6 o'clockCalibre or year of manufacture
CentrePrimer — Berdan or Boxer, and any seal colour

Research notes

After the introduction if the 44 Magnum in 1956, few companies as well as shooters (except Elmer Keith and Skeeter Skelton) recognized the need for a .40 cal cartridge that could operate between the Elmer Keith brainchilds, namely the 357 Magnum and the 44 Magnum. Keith convinced Remington and Smith & Wesson to develop the 41 Magnum, but at roughly the same time Colt engineer Bob Roy developed a .40 cal. cartridge that was made by cutting down 30-30 Win cases and loading them with a .40 cal. bullet. They contracted Winchester to produce the cases for them and loaded them with a 200 gr.GM flat tip lead bullet. In this case, Remington got the drop on the folks at Colt and launched the 41 Magnum ahead of the Winchester version, effectively ending the whole project. It did not enter commercial production and only a few test lots were manufactured. Except for the smaller rim diameter, the 400 Colt Magnum is the same as the 41 Rem Mag. (Erlmeier, Brandt Ref. 381)

Provenance

2016Catalogued in the collection
2026Record last revised · 2026-03-01