.22 TCM

22TCM
From left: .22 TCM, FN 5.7×28mm, .223 Remington
TypePistol/Rifle
Production history
DesignerFred Craig
Specifications
Parent case5.56×45mm NATO
Case typeRimless, bottleneck
Bullet diameter0.224 in (5.70 mm)
Neck diameter0.255 in (6.48 mm)
Shoulder diameter0.362 in (9.19 mm)
Base diameter0.376 in (9.55 mm)
Rim diameter0.378 in (9.60 mm)
Rim thickness0.045 in (1.1 mm)
Case length1.022 in (26.0 mm)
Overall length1.265 in (32.1 mm)
Case capacity15.2 gr H2O
Ballistic performance
Bullet mass/type Velocity Energy
40 gr (3 g) Pointed flat nose 2,800 ft/s (850 m/s) 696 ft⋅lbf (944 J)
40 gr (3 g) Pointed flat nose 2,070 ft/s (630 m/s) 381 ft⋅lbf (517 J)
Test barrel length: 22.75" rifle (higher velocity) and 5.0" pistol (lower velocity)

The .22 TCM (Tuason, Craig, Micromagnum) is a proprietary bottlenecked rimless cartridge derived from a 5.56×45mm NATO (.223 Remington) parent case. It was developed by custom gunsmith Fred Craig in collaboration with Martin Tuason, the President of Rock Island Armory (RIA) and Armscor. The cartridge is primarily used in Rock Island Armory M1911 pistols and the M22 TCM bolt-action rifle.

Initially known as the .22 Micro-Mag, the .22 TCM is conceptually similar to other bottlenecked pistol cartridges, such as the 7.62×25mm Tokarev and the FN 5.7×28mm. The design prioritizes high velocity and reduced recoil by trading bullet mass for speed, making it suitable for various applications.