I saw a post on Rokslide awhile back about someone getting told braces were now ok by CPW. So I called and initially I was told they were ok but with some hesitation by a person at the Ft. Collins office. I then asked if I could talk to one of the officers for my GMU. I ended up going down the rabbit hole and speaking with a few CPW officers. They would not give a straight answer for braces and kept deferring to another officer. The final officer I spoke with was the local expert on methods of take (Front Range Area). He basically said if they feel it's a stock you get a ticket. I asked if he was familiar with SIG Style AR braces and he simply redirected to the previous statement. After getting the feeling that everyone at CPW is eager to write tickets, I decided to go the route of a KAC Tube and Shockwave Blade. I remove the blade for hunting and just using a bare pistol tube. A bare pistol tube was the only thing I got an actual "That's legal" from CPW.
As to why not just a 16". I've done that and it works, but a 17.5" effective length with suppressor makes for a very handy and pack-able setup when hunting burns with lots of dead fall.
Are you also the guy writing BATFE asking for clarification on every single decision they've ever published? Good Lord.
Lessons cost money. Good ones cost lots. -Tony Beets