Introduced about 2014, the 22 TCM uses a significantly shortened 222 family case. Designed to work in a 1911 Colt Pistol, this round generates high velocity with a light bullet and therefore has very modest recoil. Special alterations to the basic 1911 are necessary to get that recoil-operated gun to function with so little momentum generated by recoil of the accelerating bullet and propellant. But, it can be done. Developed muzzle energy with the 22 TCM is significant for a pistol because the round works at relatively high pressure, 38,000 psi and has relatively significant capccity. This is much higher than most other 1911 chamberings but is safe because of the smaller case diameter and lower momentum generated by the light bullet. The limited factor in usable chamber pressure is probably the requirement that the case cannot stick at all in the chamber, otherwise, even higher pressure would likely be feasible. I remain unsure of the value of the 22 TCM but others have found it interesting and worth working with. To me, the most exciting thing about it is the potential for sharpening the case shoulder and using the case as the basis for a fine modern 17-caliber minimalist varminting cartridge; it has ideal capacity and works in rifles with the 223 bolt-face. The heritage of this case dates to the 38 Colt cartridge of the 1860s and before that with the 1839 introduction of the 36 Colt Paterson cap-and-ball Revolver.