The Convict, The Floating Chamber, and The Colt Ace

What do you do when you need a full-heft, realistically-recoiling .22 caliber training pistol? Why, call up convicted murderer David Marshall (later called “Carbine”) Williams, of course! The 1930s were a different time, when convicts were encouraged to use the prison machine shop to create inventive weapons for fighting the enemies of democracy, or just to make Winchester a buck.

Grant Cunningham covers the remarkable floating chamber design of the Colt Ace training pistol, it’s development and history, over at his blog. Follow the link to see some impressive high speed footage of its operation (in gif form), and learn a bit of history behind the remarkably innovative operating mechanism.


H/T, Grant Cunningham, Daniel Watters

Nathaniel F

Nathaniel is a history enthusiast and firearms hobbyist whose primary interest lies in military small arms technological developments beginning with the smokeless powder era. In addition to contributing to The Firearm Blog, he runs 196,800 Revolutions Per Minute, a blog devoted to modern small arms design and theory. He is also the author of the original web serial Heartblood, which is being updated and edited regularly. He can be reached via email at


  • FourString

    can we still buy one?

    • Anonymoose

      Walther still makes Colt-branded .22 1911s.

      • Dan Atwater

        That’s not really the same thing. Pretty sure the Walther .22s do NOT replicate the felt recoil of a .45, which is kind of the whole point of this article.

        This thing is pretty cool too, had no idea it existed.

        • Anonymoose

          Unfortunately the real Service Ace has been out of production for quite a while. :C

    • It would take some searching but they are still out there.

    • Seth Hill

      The online gun auctions have them, prices appear to be starting about $1100.

  • dan citizen

    Great article, there goes my next hour 🙂

  • guest

    Finally… a good article on TFB. Never heard of this (floating chamber) before, but it is basically a recoil augmenter much like the one used on Vickers MG and MG-42, just that instead of having the whole barrel recoil with more force here it’s only a bushing inside the barrel.