| Caliber .50 GI, Model No 1. | |
|---|---|
 | |
| Type | Semi-automatic pistol |
| Place of origin | United States |
| Production history | |
| Designer | Alex Zimmermann |
| Manufacturer | Guncrafter Industries |
| Variants | Model No. 2, Model No. 3, M1911 |
| Specifications | |
| Mass | 2.5 lb (1,134 g) |
| Length | 8.5 in (216 mm) |
| Barrel length | 5 in (127 mm) |
| Cartridge | .50 GI |
| Action | Locked breech, semi-auto |
| Rate of fire | Semi-automatic |
| Muzzle velocity | 875 ft/s (267 m/s) |
| Effective firing range | 75 yd (69 m) (FM 23–35 of 1940) |
| Feed system | 7 rounds (standard-capacity magazine) |
| Sights | Heinie, fixed, 3-dot Trijicon |
The Guncrafter Industries Model No. 1 (Or M1) is a variant of the widely popular M1911 handgun, modified for the .50 GI cartridge. John Browning's 1911 .45 ACP has been used for many cartridges over the past century. In every instance the cartridge used a bullet with a diameter that was the same or smaller than the original .451". Both the Desert Eagle and the LAR Grizzly have been offered in cartridges of .50 caliber. Both are large cartridges requiring a large, heavy pistol.
The Model No. 1 is basically an M1911 with external dimensions the same as a standard 1911, however it fires a .50 GI round. Although the Model No. 1 is the same size externally, the slide will not fit on a standard 1911 frame as other modifications have been made to accept the .50 GI barrel and slide. However, it is possible to convert the Model No. 1 to .45 ACP, as a .45 ACP conversion unit is available for the .50 GI frame.
The .50 GI is not in the magnum class and works at the same pressures as the .45 ACP. The cartridge uses the same rim size as the .45 ACP and a .45 shell holder can be used for reloading. This new brass is made by Starline Brass and is slightly shorter than a standard .45 ACP. The magazine well in the grip frame has thinner walls than a standard M1911 to accommodate the .50 GI's wider magazine, and the frame feed ramp is contoured with a more open radius for the larger-diameter .50-caliber bullet. Both are machined from heat-treated forgings, and the Model No. 1's hammer and sear are machined from tool steel.