Colorado bowhunt broadhead rules
Colorado Parks and Wildlife (CPW) is one of the more permissive Western states on broadhead type. Both fixed and mechanical heads are legal for big game archery hunts, subject to minimum cut and blade count. The complexity in Colorado is the draw-unit system (Unit 61, 62, 20, etc), not the broadhead rules themselves.
The rule
CPW big game regulations (see the annual Big Game brochure and the Colorado Wildlife Commission regulations, 2 CCR 406-2 and 406-3) require: broadheads must be at least 7/8 in in width, must have at least two steel cutting edges, and must be metal (no ceramic, glass, or plastic). Both fixed and mechanical (expanding) broadheads are legal.
Blade count and minimum cut
Two cutting edges minimum. 7/8 in minimum cut width. Steel blades required.
Species restrictions
The broadhead rule applies to elk, deer (whitetail and mule), pronghorn, moose, black bear, and mountain lion. Colorado runs a draw system for premium units (Unit 61 has been the most-referenced elk unit on Rokslide and Archery Talk for years). Bowhunter education is required for any archery license, plus a stamp fee.
What this means in practice
Almost every commercial broadhead on the market is legal in Colorado. The 7/8 in minimum cut rules out very compact heads (some 3/4 in field-point-style heads for practice), but every mainstream head (Rage 2 in, SEVR 2.0, Iron Will S100 at 1-1/16 in, Slick Trick Magnum at 1-1/8 in) is legal. Focus on your draw-unit application and preference points, not head type.
Source
Colorado Parks and Wildlife at cpw.state.co.us/hunting/big-game.