A lightweight structural steel frame assembly uses nail pins as structural fasteners between structural frame members, such as studs, joists, channels and tracks. The structural frame assembly may be substantially free of screws, rivets or other prior art fasteners known for making structural connections between light gauge steel structural members. Structural steel in the range of about 10 to 30 gauge is used for the light gauge structural steel members, or more preferably, in the range of about 14 to 25 gauge. The nails pins are made of a high-strength, ductile steel formed with a ballistic tip for piercing the steel and may include a knurled shank. The nail pins are arranged in a defined pattern.