I have seen a couple references to making detachable rear sights from the carry handle. Are they referring to cutting them down? Is this to free up some rail space?
Thanks, BL

Yes, you can cut down your detachable carry handle to a fixed BUIS.
It leaves you space to mount optics like Eotechs or Aimpoints in front of them.
Also, since many flattop AR's come with a carry handle, it saves you the expense of buying a seperate BUIS.
Here's a link from AR15.com on how to do it:

How-to Chop your Carry Handle into a BUIS - AR15.COM

Unfortunately it's an old thread and a lot of the images are missing, but go through the whole thing and you'll get the idea.